# Londinium 1 brew temperature testing



## AndyS

I received my Londinium 1 three weeks ago, and it is a beautifully crafted machine. I don't remember seeing any brew temperature data online, so I hooked up a Scace device and began testing. When the results were a little hard to understand, I temporarily strapped a second thermocouple to the outer surface of the group. This made the actual brew water temperature much easier to predict, since the superheated boiler water is cooled by the group before it hits the coffee bed.

The procedure for Scace testing was as follows:

1. remove the portafilter from the group for ~30 sec to account for time spent dosing and tamping

2. reinsert the portafilter into the group

3. smoothly pull the lever to the full down position and allow 3 grams of water to pass through under boiler pressure only (simulating a short preinfusion)

4. smoothly raise the lever and allow the "extraction" to proceed under spring pressure until an additional 40 grams of water had come through

5. record initial and final group surface temperatures plus peak and final brew water temperatures

Notes:

a. The 3 grams and 40 grams of water are somewhat arbitrary values, but seemed to correspond with my actual shotmaking technique

b. Per Londinium instructions, the tests were performed without any group flushes and at random intervals between shots

c. Pressurestat was set to cut in at about 1.0 bar and cut out at about 1.2 bar. This corresponds to an average boiler temp of about 122C or 252F.

Some of the data is summarized in the graphic below. Please excuse the Fahrenheit measurements; since I am in the US, those are the units I normally use.









Comments:

1. These shots were measured over the course of several days at random times. Other than an open-group flush after the boiler first came up to pressure in the morning, I made no attempt to control group temperature.

2. There is a fairly linear relationship between initial group temp and average brew water temp. This makes group temp a good predictor of average brew water temp.

3. Brew water temp drops an average of about 10F (6C) during the course of a shot.

4. The most curious result was the "hole" in both group temp and the resulting brew water temp that you see on the graph. It seems that the thermosiphon "flips" at group temperatures between 183F and 190F (84C to 88C). In this group of 24 random measurements, no shots appeared in that range. A different pressurestat setting might shift this range up or down.

5. So far I've made only a limited number of direct taste comparisons between otherwise-identical shots prepared on the L1 vs my Speedster. Many of the L1 shots have compared favorably, but the Speedster shots have been more consistent. Looking at the data on the graph, this might be expected.

6. I would be very interested to see this type of data from other L1 users.


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## aaronb

Very interesting, thanks for taking the time to do this.

I know a lot of users on HB were interested in this data, and if you are in the USA I guess you already posted it there too? (I stopped following the L1 thread there due to all the trolling so apols if you have already).

I wander if the fact you have the 110v version with the lower wattage element makes a difference too?


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## AndyS

aaronb said:


> I know a lot of users on HB were interested in this data, and if you are in the USA I guess you already posted it there too?


Actually not, I don't post there anymore.



aaronb said:


> I wander if the fact you have the 110v version with the lower wattage element makes a difference too?


I don't think the lower wattage makes much of a difference. Oftentimes when pulling a shot, the element is off the whole time.


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## RoloD

> So far I've made only a limited number of direct taste comparisons between otherwise-identical shots prepared on the L1 vs my Speedster.


 Personally, I'd be rather more interested to hear about this than the hard data. What would be interesting is to correlate the subjective report on both machines with the Scace measurements.


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## painty

Although the points are intrashot averages, am I right in thinking only 1/3 of the pulls were in the zone? Perhaps a flush would tighten the grouping up a bit?


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## lookseehear

RoloD said:


> Personally, I'd be rather more interested to hear about this than the hard data. What would be interesting is to correlate the subjective report on both machines with the Scace measurements.


Surely it's pretty indisputable that water temperature directly affects the flavour, therefore having a consistent start point will correlate with having a consistent flavour? It's very difficult to compare subjectively as everyone's palate and preferences are different.


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## RoloD

lookseehear said:


> Surely it's pretty indisputable that water temperature directly affects the flavour, therefore having a consistent start point will correlate with having a consistent flavour? It's very difficult to compare subjectively as everyone's palate and preferences are different.


Well, ultimately it is only the subjective evaluations that have any meaning. Sure, temperature indisputably affects flavour, but there are many other variables other than the temperature start point and only a subjective evaluation (tasting the stuff) can tell which are most relevant. Is, for instance, temperature start point consistency more important that consistency in temperature drop? I have absolutely no idea, and the only way to answer that question is to taste the coffee.

To put it another way: compare it to the world of audio, where some think the only way to evaluate a hi-fi system is to listen to it whereas others favour objective scientific measurement. But here the analogy breaks down - there are relevant objective measures in audio (you are looking for the least distortion and colouration and the most accurate reproduction of source, even if you might prefer to listen to something that is technically less accurate) but in coffee really the only thing that matters is what the coffee tastes like.

Sure, you want a machine to produce consistent results but that is irrelevant if those consistent results don't taste good.


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## lookseehear

Personally I think purely subjective observations are pretty irrelevant unless this the same observations are made independently by a large number of people. Like I said - everyone's tastes are different so there's no point in trying to debate what tastes 'best'.

I do agree that it's interesting to compare subjective assessments with the Scace measurements but it that also has limited appeal to me unless the subjective assessments are made in an environment free from bias (ie you don't already know that it will be a 'hot' shot or a 'cool' shot before tasting).

If I understand the data that AndyS has compiled correctly it means that given the same thermostat setting the group and shot temperature varies by around 20 degrees Fahrenheit from day to day and shot to shot. I'm slightly confused by this as Reiss has long been waxing lyrical about how stable the temperature should be due to the thermosyphon and 7kg of brass in the group (he was pretty damning of other designs if I remember correctly) but these tests seem to show this isn't correct. I'm not saying that the L1 isn't capable of producing great espresso I just don't like information to be portrayed as fact when it isn't.


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## AndyS

painty said:


> Perhaps a flush would tighten the grouping up a bit?


If one can flush the right amount, it will warm up the group and raise the shot temp. So if the group is a little cool, the right flush will help. If the group is already too hot, the flush will make matters worse.

Or at least that's how it appears so far....


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## AndyS

RoloD said:


> Well, ultimately it is only the subjective evaluations that have any meaning....
> 
> ...Sure, you want a machine to produce consistent results but that is irrelevant if those consistent results don't taste good.


I agree 100%; I'm trying not to get lost in the numbers, but instead figure out how to make exceptional espresso, consistently. Undoubtedly my expectations are too high at this early stage, since I've been using a machine that costs three times what the L1 does and I've made certain mods to it for more control.

The L1 has produced some stellar shots but also a lot of mediocre ones. It is still very new to me, so I'll happily attribute all the mediocre shots to "operator error."

In the meantime, I would love to get a handle on the temperature situation so I can move on to the more interesting parameters (dose, grind, brew ratio, etc).


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## RoloD

lookseehear said:


> Personally I think purely subjective observations are pretty irrelevant unless this the same observations are made independently by a large number of people. Like I said - everyone's tastes are different so there's no point in trying to debate what tastes 'best'.


 Well, I repeat my point: objective measurements are meaningless unless correlated with taste - I think Andy's aim is to find out just why one machine produces coffee that tastes better than another. There is no objective measurement of taste, but ultimately taste is what matters.


> I'm slightly confused by this as Reiss has long been waxing lyrical about how stable the temperature should be due to the thermosyphon and 7kg of brass in the group... but these tests seem to show this isn't correct. I'm not saying that the L1 isn't capable of producing great espresso I just don't like information to be portrayed as fact when it isn't.


 But what are you comparing these figures to? Any machine is going to experience variations in temperature during its use - it's a dynamic system where temperature is not intended to be stable - it is part of the principle of a lever machine that temperture drops during the course of a shot then recovers. Is an HX machine that requires cooling flushes going to produce, on paper, more consistent results? Are other lever machines going to produce more consistent results? Is PID controlled temperature-profiled system going to produce more consistent results? These figures need to be judged in context.

Additionally, measurement of temperature of an espresso system is not a trivial matter. The most crucial measurement - the temperature of the water as it passes through the coffee - is also the most difficult to assess. And other factors like water pressure and consistency of pressure may also be very important. There is no objective way knowing which are the crucial factors without tasting the coffee.


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## garydyke1

lookseehear said:


> Surely it's pretty indisputable that water temperature directly affects the flavour, therefore having a consistent start point will correlate with having a consistent flavour? It's very difficult to compare subjectively as everyone's palate and preferences are different.


Temperature stability + PID = happy days


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## The Systemic Kid

RoloD said:


> There is no objective way knowing which are the crucial factors without tasting the coffee.


In the pursuit of scientific endeavour and rigour, subjective observation must be ignored - better remove the human element from the equation altogether!


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## garydyke1

RoloD said:


> - I think Andy's aim is to find out just why one machine produces coffee that tastes better than another. There is no objective measurement of taste, but ultimately taste is what matters. [/i]


Isnt is better to find out why a singular machine makes great coffee some of the time and medicore coffee other times?....and why this would be. I assume Andy tasted the espresso and knowing he has a solid history of respected coffee experience


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## Glenn

garydyke1 said:


> I assume Andy tasted the espresso...


Not in this instance. A Scace device cannot be filled with coffee and therefore the tastes for each set of figures is not possible.

A Scace should only be used with a clean grouphead.

Pressure and temperature only can be measured with a Scace.

Taste requires coffee to be present.

I would have liked to see the tests conducted in a controlled environment.

Surely ambient air temperature is an influencing factor?

If there is a dead spot in the figures, how about conducting further tests by adding more control points or adjusting the pressurestat?


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## The Systemic Kid

Came across this - long and detailed but worth the effort - particularly the reference to what defines standards we tend to accept?

http://londiniumespresso.com/blogs/londinium-espresso-blog/2708852-art-versus-science


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## garydyke1

Glenn said:


> Not in this instance. A Scace device cannot be filled with coffee and therefore the tastes for each set of figures is not possible.
> 
> A Scace should only be used with a clean grouphead.
> 
> Pressure and temperature only can be measured with a Scace.
> 
> Taste requires coffee to be present.
> 
> I would have liked to see the tests conducted in a controlled environment.
> 
> Surely ambient air temperature is an influencing factor?
> 
> If there is a dead spot in the figures, how about conducting further tests by adding more control points or adjusting the pressurestat?


Sorry , I meant in general for him to have made his opinion on varying results with all else being even and consistant


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## Glenn

Agreed. Just a little more context for all who might not have used a Scace before.


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## lookseehear

RoloD said:


> Well, I repeat my point: objective measurements are meaningless unless correlated with taste - I think Andy's aim is to find out just why one machine produces coffee that tastes better than another. There is no objective measurement of taste, but ultimately taste is what matters.


I'll also repeat my point - *purely* subjective measurements are (in my opinion) meaningless for the purposes of comparison - one man's God shot is another man's sink shot. You can tell me that the L1 produces the best espresso you've ever tasted but it's pretty clear our tastes are different so there's a limited amount I can take from that.



RoloD said:


> But what are you comparing these figures to? Any machine is going to experience variations in temperature during its use - it's a dynamic system where temperature is not intended to be stable - it is part of the principle of a lever machine that temperture drops during the course of a shot then recovers. Is an HX machine that requires cooling flushes going to produce, on paper, more consistent results? Are other lever machines going to produce more consistent results? Is PID controlled temperature-profiled system going to produce more consistent results? These figures need to be judged in context.


I'm comparing it to temperature studies of other machines that produce repeatable results within a couple of degrees. I didn't say that a flat temperature profile is important but if you're spending a decent amount of money on a machine I think producing consistent results (meaning a consistent starting point and consistent temperature profile) is important. If you make one shot after another and one tastes better than the other, how do you know whether it's the water temp, temperature profile, or whether it's something like grind and distribution? If you can isolate some of these variables you can understand better how (or whether) the other variables effect the quality of the espresso.



RoloD said:


> Additionally, measurement of temperature of an espresso system is not a trivial matter. The most crucial measurement - the temperature of the water as it passes through the coffee - is also the most difficult to assess. And other factors like water pressure and consistency of pressure may also be very important. There is no objective way knowing which are the crucial factors without tasting the coffee.


It might not be a trivial matter but a Scace is unlikely to be wrong by more than a few degrees so for the purposes of this conversation it is probably good enough. Like I said above, in order to know how a variable effects the flavour of the espresso you have to try and keep all but one variable consistent then taste the differences (subjective as well as objective) in flavour with a known change in a variable. This is pretty simple stuff. The pressure/pressure profile may be very important but how would you ever know unless you can isolate those variables and taste the differences (something which isn't possible with a 20 degree F variation in water temperature).

To be perfectly honest, it doesn't concern me too much whether the L1 can produce water that is a stable temperature. What I am concerned about is anyone trying to pretend that it doesn't matter. If all that matters is having a spring group then why should anyone buy an L1 over a cheaper lever machine?


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## lespresso

hi andy

would you mind posting a brief video clip showing you pulling a shot in the way you did for the data set reported above?

(you have interrupted the thermosiphon; you are the first customer to achieve this)

the tightly grouped data points 'above' the gap are observed when the thermosiphon is functioning normally

i note that you have also turned the boiler pressure down from the factory setting of 1.3 bar

best

reiss.


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## AndyS

lespresso said:


> hi andy
> 
> would you mind posting a brief video clip showing you pulling a shot in the way you did for the data set reported above?
> 
> (you have interrupted the thermosiphon; you are the first customer to achieve this)


Sure, I will do so as soon as I get a chance.



lespresso said:


> the tightly grouped data points 'above' the gap are observed when the thermosiphon is functioning normally
> 
> i note that you have also turned the boiler pressure down from the factory setting of 1.3 bar


As I told you via email on 3/17 and again on 3/19, I had to turn down the pstat because as received from the factory, the safety relief valve was hissing and sputtering at the standard setting.

Question: when you say the factory setting is 1.3 bar, does that mean the heater cuts in at 1.3 (cutting out around 1.5 bar) or does it mean the heater cuts out at 1.3 bar (cutting in around 1.1 bar)?

Also: if you think that turning down the pstat may be impeding the ability of the thermosiphon to operate properly, I will try turning it up again to see if the relief valve will behave.


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## AndyS

The Systemic Kid said:


> Came across this - long and detailed but worth the effort - particularly the reference to what defines standards we tend to accept?
> 
> http://londiniumespresso.com/blogs/londinium-espresso-blog/2708852-art-versus-science


The link that Reiss posted on his blog (an article by Michael Teahan) is very good, but it is also very old. Similar thoughts have long been posted by others, including this six year old blog piece by someone you may know.









Also, the section Reiss quotes about WBC standards is obsolete. The current "WCE standards" (not WBC anymore) no longer put a premium on flat temperature profiles. The machines are judged on being able to produce shot with repeatable *average brew temperatures* under a variety of duty cycles. That means a declining temperature profile is fine, as long as the machine can produce the same profile repeatedly.


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## lespresso

i refer to my email of 8 march Andy:

'You are correct

It is the safety valve

If there is a piece of grit in the solenoid it can cause this

To address turn the machine on and open the water tap

Allow lots of water to be forced out of the hot water tap as the machine heats up

When the pump kicks in to refill the boiler, close the water tap

This should flush any grit out of the solenoid

Reiss'

This isn't an issue specific to the L1 - it will occur on any machine if a piece of grit (e.g. a piece of carbon filter particulate) passes through the solenoid as it is closing, although the two other L1 customers that reported this issued both have plumbed in machines where the likelihood of overfilling the boiler is much greater if the solenoid is unable to fully close as the line pressure is constant whereas a pump stops on a pump & tank model when the signal is given to close the solenoid, so your machine is the only tank & pump machine i know of where this issue has arisen

I probably should have added, repeat if necessary

The safety valve opens at 1.8bar and is factory tested and certified to open at this pressure, so a pressure stat setting of 1.3 bar should work just as well on your machine as it does on the other 86

If you could post here a video of you pulling a shot in the manner in which you were for the above data set i think we can get to the bottom of the matter fairly quickly - L1 is one of the most simple machines on the market

Alternatively, if you want to expound on how much you know about coffee, we could do that instead

I note with interest that you felt the need to modify Kees van der Westen's Speedster too

Best

Reiss


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## AndyS

lespresso said:


> if you want to expound on how much you know about coffee, we could do that instead


Touchè, Reiss! A blow well struck! ;-)



lespresso said:


> i refer to my email of 8 march Andy:
> 
> 'You are correct
> 
> It is the safety valve
> 
> If there is a piece of grit in the solenoid it can cause this
> 
> To address turn the machine on and open the water tap
> 
> Allow lots of water to be forced out of the hot water tap as the machine heats up
> 
> When the pump kicks in to refill the boiler, close the water tap
> 
> This should flush any grit out of the solenoid
> 
> Reiss'
> 
> This isn't an issue specific to the L1 - it will occur on any machine if a piece of grit (e.g. a piece of carbon filter particulate) passes through the solenoid as it is closing, although the two other L1 customers that reported this issued both have plumbed in machines where the likelihood of overfilling the boiler is much greater if the solenoid is unable to fully close as the line pressure is constant whereas a pump stops on a pump & tank model when the signal is given to close the solenoid, so your machine is the only tank & pump machine i know of where this issue has arisen
> 
> I probably should have added, repeat if necessary
> 
> The safety valve opens at 1.8bar and is factory tested and certified to open at this pressure, so a pressure stat setting of 1.3 bar should work just as well on your machine as it does on the other 86


Per your instructions, I did perform this maneuver several times, although it puzzled me how flushing the fill solenoid could clear a piece of grit from the safety valve.

Whether it was that procedure, the passage of time, or the lower pstat setting, my safety valve has been quiet for the past week.



lespresso said:


> If you could post here a video of you pulling a shot in the manner in which you were for the above data set i think we can get to the bottom of the matter fairly quickly - L1 is one of the most simple machines on the market


It is a little embarrassing to post a video after watching Roland Denning's work, but per your request,





[/QUOTE]

I have made mods to every espresso machine I've ever owned; FWIW, the ones to Kees's machine were quite minor.

More on topic: because I have lowered the pstat setting, there is less energy in the system overall. Perhaps that means the thermosiphon is less effective in performing its function. It could explain part or all of what I'm seeing vs the other 86 machines that may operate more consistently.

I haven't tried going back to a higher setting yet, in part because I was waiting to hear back from you what the factory setting was. The other reason I haven't done it is because I have a brand new data logger that I'm trying to get up and running. This would produce graphs of boiler temperature that would be objective and more useful than verbal descriptions.


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## The Systemic Kid

AndyS said:


> Touchè, Reiss! A blow well struck


Hmmm. Interesting choice of language.


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## BLrdFX

Andy:

Why was the Green Fill Indicator Lamp on during the entire video that you Posted?

Stephen


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## AndyS

BLrdFX said:


> Andy:
> 
> Why was the Green Fill Indicator Lamp on during the entire video that you Posted?


Hi Stephen:

On one of the forums someone mentioned that they had rewired the green light to indicate On/Off status rather than Pump On. I thought that was a good idea since it's damn obvious when the vibe pump comes on! Other than that and experimenting with different pstat settings, the machine is straight factory stock.


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## BLrdFX

AndyS said:


> Hi Stephen:
> 
> On one of the forums someone mentioned that they had rewired the green light to indicate On/Off status rather than Pump On. I thought that was a good idea since it's damn obvious when the vibe pump comes on! Other than that and experimenting with different pstat settings, the machine is straight factory stock.


Yes, an "ON" indicator light is a good idea! Where exactly did you tap into the power?

I run mine on house line pressure so no pump necessary and it allows me to stash stuff(clean wrapped stuff) in the tank


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## AndyS

BLrdFX said:


> Yes, an "ON" indicator light is a good idea! Where exactly did you tap into the power?
> 
> I run mine on house line pressure so no pump necessary and it allows me to stash stuff(clean wrapped stuff) in the tank


I got power off the back of the main On/Off toggle switch using one of those piggyback quick connect terminals.

I'd be careful about stashing stuff in the tank. If burglars notice you have a plumbed in machine, they always look to see if gold and jewels are hidden in the unused tank.


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## BLrdFX

AndyS said:


> I got power off the back of the main On/Off toggle switch using one of those piggyback quick connect terminals.
> 
> I'd be careful about stashing stuff in the tank. If burglars notice you have a plumbed in machine, they always look to see if gold and jewels are hidden in the unused tank.


That's an easy location! Thanks.

I stashed the Vibe Pump and some fittings in the tank so I they would not go adrift. Yes, the psychology of putting things out of a predators grasp is interesting. The most expensive things in my home is the coffee gear, much to my wife's dismay.


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## AndyS

Before getting into a further discussion of my L1 machine's temperature performance, I should say that IMHO the L1 is a great-looking machine (the group is drop-dead gorgeous), the size is terrific for the home, and the price is excellent. *Most importantly, a few of the shots I've pulled on it are really terrific, with flavors appearing that have not been appearing on my Speedster shots.*

All this motivates me to try and figure out why I'm having temperature management issues that others don't seem to have, or at least don't seem to notice. A few of you kind strangers have chimed in with suggestions, but Reiss, it's you that knows the machine intimately, and it's you I look to in figuring out what's going on.



lespresso said:


> The safety valve opens at 1.8bar and is factory tested and certified to open at this pressure, so a pressure stat setting of 1.3 bar should work just as well on your machine as it does on the other 86


I agree, it should -- but it doesn't.

Anyway, last night I readjusted the pstat so the heater cuts in around 1.2 bar and cuts out around 1.4 bar. Just after cut out I could hear the safety valve faintly sputtering. I didn't want to set the pstat any higher.

After doing that I got the datalogger hooked up to the L1 and left it on for about 20 hours. You can see the result below, although it's hard to see because the forum makes the image so tiny. (Is there a trick to getting it bigger?)

The green and blue traces are the group temperature taken in two places. Yellow is the room temperature and the red spikes are the Scace device reading shots.









What is sad to see is the group temperature (green and blue) drifting around, because the shot temperatures drift with the group. In this group of nine shots the peak shot temperature was 217F in one shot at 6:29am and only 189.5F in another shot at 8:00am. That's a difference of 27.5F from hot shot to cool shot, and frankly, that sucks.

Reiss, do you think the thermosiphon is plugged or otherwise messed up? Perhaps the same junk that got in my safety valve also got in the thermosiphon pathway?


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## BLrdFX

This might sound like a dumb question, but what is your line voltage doing when the temperature drops?


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## AndyS

BLrdFX said:


> This might sound like a dumb question, but what is your line voltage doing when the temperature drops?


I haven't looked at that; but since the heater is able to bring the boiler back up to temperature with a few seconds, I don't think voltage or heater rating is at all a factor at these extremely low production rates.


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## BLrdFX

AndyS said:


> I haven't looked at that; but since the heater is able to bring the boiler back up to temperature with a few seconds, I don't think voltage or heater rating is at all a factor at these extremely low production rates.


I see your point.


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## The Systemic Kid

Liked the homage to The Clash in the video - nice touch. Thought it would be a good idea to put a link to it on this forum:






Andy, the clip shows the LI temp at beginning of extraction running at 93.3c which is, if I recall, what it should be at beginning of extraction. Whist not impugning your data, it would be helpful to see a video test of the actual fluctuating results you are getting.


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## iroko

Could it be your vacuum breaker that's spluttering and not the safety valve.


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## lespresso

if you dwell the piston seals over the inlet ports (esp pulling lever down, you may also be able to do it letting the lever back up) you run the risk of air being sucked down past the seals and into the inlet ports and into the thermosiphon

air in the thermosiphon will cause it to stall

when you pull your shots don't dither with the seals over the inlet ports and it won't happen

i suspect when you are doing your little flush (let me reiterate: it is not required) that you are pulling down the lever until you hear the hiss of water rushing into the brew chamber & dwelling at that point for a bit; if you want to stall the thermosiphon this is a good way to do it

use the machine in accordance with the instruction manual and the thermosiphon won't stall - just like the other 86 machines that have not reported this issue

if you are an L1 customer and are left wondering how do i know if I've stalled the TS, the good news is you don't need a scace to determine this

just place your (warm - not cold) hand on the side of the group. if you are forced to remove your hand after about 5 seconds because of the heat the TS is working as normal

if you are able to leave your hand on the side of the group without undue discomfort then it is likely that you have stalled the TS

to reiniate the TS pull the lever down to the lock out position and let say 300mL escape, then return the lever to the resting position

leave the group for a good 5 minutes to heat back up evenly


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## AndyS

The Systemic Kid said:


> Andy, the clip shows the LI temp at beginning of extraction running at 93.3c which is, if I recall, what it should be at beginning of extraction. Whist not impugning your data, it would be helpful to see a video test of the actual fluctuating results you are getting.


I appreciate your suggestion, but I'm not sure exactly what you want a video of. The data logs show a few one-minute periods of action spread out over many hours of nothingness. Occasionally a digit on the temperature display might change. This would make early Andy Warhol movies look fabulously exciting.


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## AndyS

iroko said:


> Could it be your vacuum breaker that's spluttering and not the safety valve.


No, it's actually the safety valve (see photo).


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## AndyS

lespresso said:


> i suspect when you are doing your little flush (let me reiterate: it is not required) that you are pulling down the lever until you hear the hiss of water rushing into the brew chamber & dwelling at that point for a bit; if you want to stall the thermosiphon this is a good way to do it


I'm not sure why you think I'm doing a "little flush," whatever that is. I tried it early on but gave it up. I sometimes have done a 450ml flush (per your instructions) if the machine has been on only for a short while and I'm trying to get the group temp up.



lespresso said:


> if you are an L1 customer and are left wondering how do i know if I've stalled the TS, the good news is you don't need a scace to determine this
> 
> just place your (warm - not cold) hand on the side of the group. if you are forced to remove your hand after about 5 seconds because of the heat the TS is working as normal
> 
> if you are able to leave your hand on the side of the group without undue discomfort then it is likely that you have stalled the TS


If you look at the temperature graphs that I posted you may be able to discern that the group surface temp varies from ~160F to ~195F. I personally couldn't comfortably hold my hand on the group for 5 seconds even at the lowest temp. So by your test it is clear that my TS is not stalling.



lespresso said:


> use the machine in accordance with the instruction manual and the thermosiphon won't stall - just like the other 86 machines that have not reported this issue


Reiss, I appreciate how difficult it is to solve machine problems merely from written descriptions. However, I believe I am using the machine in accordance with the instruction manual -- to the letter. Just because 86 others have not reported this issue does not mean there is no issue with my machine.

I have seen no objective data to back the claim you make on your video:



> The Londinium 1 is phenomenally stable. It will sit at a constant temperature indefinitely. There's no need for a cooling flush, there's no need for a warming flush.


Could you please supply some data? Here is more of mine:


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## lespresso

ship it back to us for a full refund if you wish.


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## sjenner

Interesting thread... How does the coffee taste Andy?


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## lookseehear

AndyS said:


> I have seen no objective data to back the claim you make on your video:
> 
> "The Londinium 1 is phenomenally stable. It will sit at a constant temperature indefinitely. There's no need for a cooling flush, there's no need for a warming flush."


I'm interested in this. Surely you can't make assertions that the group temp is stable without some evidence? I'm not saying there isn't any I'm just wondering where the 'facts' come from.


----------



## lespresso

hi look see hear

since you profess to be so interested in the L1, and since you appear to be in London, why don't you bring a bag full of scace (& electron microscopes if you think it will help) and judge for yourself

Central line, Greenford, meet you at the station


----------



## fatboyslim

Can I bring a big hadron collider? All of this measuring seems immaterial to me so long as the shots taste good!

I may notice a slight difference in shot flavour if I make a second espresso immediately after a first on my cherub but they will both taste excellent!


----------



## rodabod

I think it's a good idea to see measurments from different sources given that it's very easy to mis-measure. Every measurement I've seen made of the Gaggia Classic has varied widely, some saying that the temp varies widely with the thermostat, the others saying it actually stays stable, and others saying that the temp continually drops severely during pour.

The only way you can compare results to each other is to measure in exactly the same way.


----------



## RoloD

I think attempts to work out, scientifically, what makes one machine better coffee than another are laudable. But these results do have to be viewed in context.

Are these results being compared against other lever machines or against pump machines? It is possible that lever machine Scace measurements may be less consistent than pump machines but the coffee still tastes better. Is Andy's machine performing differently from other Londiniums? Is there a flaw in the measurement process?

Nearly every LI owner seems delighted with the results and no one, in subjective reports, has complained about inconsistency - quite the opposite, in fact. So how do we make sense of objective measurements that present a different view?

I'm not sure, to be honest. I'm certainly delighted with the coffee I get out of my Londinium. It's very straightforward to use and very forgiving - it's actually hard to get a bad shot out of it, and when I've had a disappointing to shot, it's usually down to error on my part (usually poor distribution - probably the most important factor I've found in getting consistent results).

I'd rather Andy had started with a subjective report - what the coffee actually tastes like and how that compares to other machines - then using measurements to discover why it tastes better or worse or variable. As I said before, measurements on their own aren't very meaningful if they don't correlate with subjective impressions. It's whether shots taste consistent, not whether they measure consistent that is the important thing.


----------



## 4085

Rolo, does temperature stability not feature quite highly on the reasons why to choose an L1 list though?


----------



## RoloD

dfk41 said:


> Rolo, does temperature stability not feature quite highly on the reasons why to choose an L1 list though?


 It does indeed.

I'm just trying to reconcile the real-world subjective reports with these Scace measurements. There are a number of different answers to explain the disparity:

1) Londinium I owners are a little self-deluded

2) Andy's measurements are wrong

3) Andy's machine is non-typical

4) Andy's measurements are correct, but not as relevant as they appear in terms of taste consistency

In no way do I want to suggest Andy is being unprofessional in his approach or method. I am not a mechanical engineer, but to measure the temperature of a dynamic system like a lever machine where this temperature is diminishing through the course of a shot, and the change in temperature is partly dependent on how the heat is diffused through the coffee itself and partly through the mass of the group is a complex matter. I remember reading other reports on measurement of the LI group itself (not using a Scace device) that the group temperature remained remarkably consistent through the day.

I don't have a Scace device, but I can tell you the espresso I make in the morning, after the machine is warmed up, does not taste noticeably different from the espresso I make five minutes or two or three hours later. I think almost every LI user will tell you the same thing. Of course, we could all be wrong.

So I pass the question back to you, David, since you owned an LI for a time. Was inconsistency something that concerned you with this machine?


----------



## coffeechap

Isn't the only important factor the mouth feel and taste of the resulting shot from the L1 which, having had many shots from the L1 is super consistent and absolutely top notch in quality. The science baffles me and to be honest is just a step to far for me, but to each their own, all that time worrying about temperature stability ( on a machine that is quite stable) is time wasted from enjoying coffee


----------



## 4085

Rolo, my machine did not produce inconsistent shots and that was not the reason I do not any longer own one. Sorry, that will not help you work out the reasoning!


----------



## RoloD

dfk41 said:


> Rolo, my machine did not produce inconsistent shots and that was not the reason I do not any longer own one.


 Thank you, David.

I will now relax and go back to enjoying the excellent coffee the LI produces and let other people worry about the measurements.


----------



## lookseehear

lespresso said:


> hi look see hear
> 
> since you profess to be so interested in the L1, and since you appear to be in London, why don't you bring a bag full of scace (& electron microscopes if you think it will help) and judge for yourself
> 
> Central line, Greenford, meet you at the station


Hi,

I don't have a scace and although I work in London I don't live in London as of last summer so it isn't just a case of hopping on a tube.

I didn't ever doubt that the L1 is capable of producing great espresso so let's get that clear from the start.

What I did *ask* is what the basis is for your statement that the group is "phenomenally stable". If I was building and selling something similar I wouldn't make assertions that I couldn't back up. If you do have some measurements to back it up then by all means post them up.

Whether group temperature stability is important in making exceptional espresso is not a part of this discussion. The facts are:


There are potential customers who believe that temperature stability is important in making repeatable exceptional espresso

You have stated (in no uncertain terms) that the group temperature of your machine is extremely stable but haven't yet given any evidence for this


It is reasonable to assume purchases might be made on the basis of assertions you have made about temperature stability (when you are spending a large amount of money then details can become deal breakers) and I don't think this is right.


----------



## lookseehear

RoloD said:


> Thank you, David.
> 
> I will now relax and go back to enjoying the excellent coffee the LI produces and let other people worry about the measurements.


You seem to do a lot of worrying about the measurements for someone who is so satisfied with their purchase.


----------



## RoloD

lookseehear said:


> You seem to do a lot of worrying about the measurements for someone who is so satisfied with their purchase.


I'm not really worried, just intrigued by the contradictions.


----------



## garydyke1

RoloD said:


> It does indeed.
> 
> I'm just trying to reconcile the real-world subjective reports with these Scace measurements. There are a number of different answers to explain the disparity:
> 
> *1) Londinium I owners are a little self-deluded*
> 
> 2) Andy's measurements are wrong
> 
> *
> 3) Andy's machine is non-typical*
> 
> 4) Andy's measurements are correct, but not as relevant as they appear in terms of taste consistency


Taking Andys quote ''The L1 has produced some stellar shots but also a lot of mediocre ones''...suggests 1) or 3) to me.


----------



## The Systemic Kid

Andy should be congratulated for attempting to bring some scientific enquiry to what is a challenging problem - what is going on temp-wise in the brew head. After all, we accept that temp stability is important to the quality of shot extraction and LI is marketed as being, 'very stable and sitting at a constant temperature'. But the variance in brew temp results Andy reports only matter if it can be proved they impact upon shot taste. What would be interesting would be to see if Andy's results could be replicated on at least one other LI - preferably more - and seeing those possible variances sampled for taste variation which, from a scientific experimental perspective, would be impossible to achieve meaningfully. Does any of this matter? Well, yes (we all want to be reassured our machine is performing consistently) and no (at the end of the day, there are too many other variables confounding the process of analysis).

In my experience, LI is capable of producing superb complex tasting shots. In the time I have had mine, when I've got the dose and grind dialled in, I have been rewarded with very good to excellent shots. I don't know if I am being perverse but I am not bothered each shot isn't espresso nirvana - the slight variation is OK with me - it makes me think the machine is like a musical instrument that needs skill and patience to get the best out of it.

For what it's worth, came across this, Anyway, we were surprised at how slowly our brand new Scace meter responded to changes in temperature. It took around ten seconds to register the actual water temperature coming through the system (C-A). The Scace then continued to read brew temperature for 3-4 seconds after the water flow was shut off completely. We experienced this over numerous tests, at different brew temperature settings. . Full entry here:

http://www.slayerespresso.com/2008/06/14/accounting-for-total-brew-temperature-stability/#more-150

.....shades of 'how many angels can you get on a pinhead??


----------



## 4085

Yep, it all gets mega complicated when the scientists get involved! At the end of the day, if you could do a blind taste of a dozen shots all pulled from the same machine, how many people could detect any of the changes brew head temp may bring? At the end of the day though, if the claim is made, then it ought to be backed up. Let the bun fight continue, meanwhile, I am slumming it on my Strega and having to suffer the potentially awful shots pulled on a machine that does not have the alleged stability of the L1.

Just to show no sour taste in my mouth, I was quite happy with most of the shots I pulled on my L1, whether or not it suffered from temperature instability.......but there again, I drink mainly milk based drinks, so what do I know?


----------



## The Systemic Kid

Really.... milk based drinks, David? Is that allowed?


----------



## GlennV

Apologies in advance then, but here's another scientist/engineer somewhat trepidatiously checking in.

I should imagine that most here, particularly Andy, are hoping that this all comes down to something being wrong with his machine - maybe something simple even (like having the wrong thermosyphon restrictor fitted?). Certainly his data suggests something like that isn't right. Measuring brew temperature is indeed tricky, but measuring the surface temperature of the group is entirely straightforward, and Andy's data shows the group returning to its equilibrium temperature with a time constant of about 3 hours. This is the problem. A quick back of the envelope calculation suggests that recovery should be at least an order of magnitude faster than this; about 15mins for a direct connection, with a well designed thermosyphon able to do rather better. To reproduce Andy's data, you need the rate of heat transfer to the group to increase as the temperature differential between it and the boiler decreases, which is backwards. As Andy notes, the thermosyphon is certainly working, since the equilibrium group temperature is high (probably too high even). It just doesn't seem to be working so well at higher temperature differentials.

Note: The 15min number comes from assuming Newton's law of cooling for the group to air heat transfer, and I've guessed 100W for the equilibrium heat loss from the group, corresponding to the element being on for around 5% of the time. I used 7kg for the mass of the group, 380 J/kgK for it's specific heat capacity and 70K for the temperature differential between the group and the air.


----------



## sjenner

GlennV said:


> ...like having the wrong thermosyphon restrictor fitted?


As I understand things the thermosyphon on the L1 is unrestricted.


----------



## GlennV

sjenner said:


> As I understand things the thermosyphon on the L1 is unrestricted.


OK. I was just going from an article on the Londinium blog "Londinium I - an open thermosiphon design" which said that it

did have a restrictor in the hot leg. The article seems to have been taken down now though, so presumably the design changed.


----------



## AndyS

lespresso said:


> ship it back to us for a full refund if you wish.


I may yet take you up on that offer, Reiss, but that would not be my first choice.

As previously stated, there is a lot I really like about this machine. To my eyes, the look and modest size are perfect for my needs. The group is a work of industrial art. My L1 does not flex excessively and I love the ability to run it off a tank or plumbed in. Most importantly, it has produced some exceptionally good shots even when pulled side-by-side with a much more expensive home machine.

Having said that, it remains my experience over quite a few years that reproducibility of brew water temperature is an important feature in being able to consistently make excellent espresso. Apparently you feel so too, as evidenced in your "phenomenally stable" comment. Yet as the graphics have shown, my L1 is very poor in that regard. I believe the temperature inconsistency is reflected in my subjective tasting of the espresso output.

That is unfortunate, and all my measurements and graphics are the first steps in an attempt to identify and ultimately fix the issue. What is even more unfortunate is that you seem to have so little interest in helping me do this. I don't know why this is so, but certainly it is your right to act as you choose.

In any event, I assume that you will pay return shipping if I decide to return the machine?


----------



## AndyS

sjenner said:


> Interesting thread... How does the coffee taste Andy?


These are not blind tasting results, but simply put:

--When the group temperature is

--When the group temperature is around 180F, the coffee is often interesting, balanced, sweet, with occasional surprising, wonderful, unique flavors.

--When the group temperature is >190F, the coffee is generally flat, relatively boring, sometimes harsh, and often has a "cooked" flavor.


----------



## sjenner

AndyS said:


> These are not blind tasting results, but simply put:
> 
> --When the group temperature is
> 
> --When the group temperature is around 180F, the coffee is often interesting, balanced, sweet, with occasional surprising, wonderful, unique flavors.
> 
> --When the group temperature is >190F, the coffee is generally flat, relatively boring, sometimes harsh, and often has a "cooked" flavor.


My palette is obviously not that cultured, but when I mess up, I usually know it before I have tasted it... as an example, I was getting terrible channeling problems with the VST baskets for a while, so I have returned to using the stock basket and my coffee tastes great again... I perform the same RDT and WDT for both, I can't explain it, so I just live with it.

I would be very disappointed if I had spent all that dosh and I was getting rubbish... Remember, this is my first coffee machine, I don't have any history like you Andy, so I am perhaps not qualified to comment.

Anyway regarding the Londinium group...

AndyS has "tested" a coffee machine, using some test equipment that is (at best) known to be slow in it's reactions...

Meanwhile a conservative estimate would be that at least 50 million people have tested it by drinking the coffee... This group has been under manufacture since somewhere around 1955, obviously with a few mods (nothing stays the same over 50+ years)... OK, some of them have different group heating set-ups, but the Faema Lambro from 1959 was a small commercial machine that used a thermosyphon, and there are/have been others.

...The rest might not be what you might find in a coffee shop, it has been designed for the home, but it is very similar to a thousand other machines.

Anyway, I just cannot see the justification for such action to be used as proof of a particular product's unsuitability...

and at my age I can happily accept that I am an analogue kind of bloke, and just enjoy the coffee, including all but the worst mistakes.

Ultimately, it doesn't really matter how expert any of us are (I'm definitely not), I would far rather accept the ongoing popularity of the output, as not spat out (measured) by those 50+ million palates.


----------



## sjenner

sjenner said:


> My palette is obviously not that cultured, but when I mess up, I usually know it before I have tasted it... as an example, I was getting terrible channeling problems with the VST baskets for a while, so I have returned to using the stock basket and my coffee tastes great again... I perform the same RDT and WDT for both, I can't explain it, so I just live with it.
> 
> I would be very disappointed if I had spent all that dosh and I was getting rubbish... Remember, this is my first coffee machine, I don't have any history like you Andy, so I am perhaps not qualified to comment.
> 
> Anyway regarding the Londinium group...
> 
> AndyS has "tested" a coffee machine, using some test equipment that is (at best) known to be slow in it's reactions...
> 
> Meanwhile a conservative estimate would be that at least 50 million people have tested it by drinking the coffee... This group has been under manufacture since somewhere around 1955, obviously with a few mods (nothing stays the same over 50+ years)... OK, some of them have different group heating set-ups, but the Faema Lambro from 1959 was a small commercial machine that used a thermosyphon, and there are/have been others.
> 
> ...The rest might not be what you might find in a coffee shop, it has been designed for the home, but it is very similar to a thousand other machines.
> 
> Anyway, I just cannot see the justification for such action to be used as proof of a particular product's unsuitability...
> 
> and at my age I can happily accept that I am an analogue kind of bloke, and just enjoy the coffee, including all but the worst mistakes.
> 
> Ultimately, it doesn't really matter how expert any of us are (I'm definitely not), I would far rather accept the ongoing popularity of the output, as not spat out (measured) by those 50+ million palates.


Mind you... saying that... I could introduce profanity at this point by drawing a similar analogy to Starbucks (sorry about the language)...

Millions drink something there everyday and apparently they don't spit it out...?

...Consider myself now limping from a bullet in my foot.


----------



## The Systemic Kid

AndyS said:


> These are not blind tasting results, but simply put:
> 
> --When the group temperature is
> 
> --When the group temperature is around 180F, the coffee is often interesting, balanced, sweet, with occasional surprising, wonderful, unique flavors.
> 
> --When the group temperature is >190F, the coffee is generally flat, relatively boring, sometimes harsh, and often has a "cooked" flavor.


Andy, for any of your subjective taste comments in relation to the above temperatures to have any credibility, they would have to have been conducted blind. Did you do that??


----------



## RoloD

To be fair to Andy, there is an anomaly here - the group temperature should not be varying that much.

If you look at reports on H-B, where (I think) two people are selling their La Marzocco GS/3 (about 3 times the price of the LI) because they prefer the output of the LI and reports from very experienced coffee drinkers have been nothing but favourable, something is not right. In fact, I have not read any other tasting reports, apart from Andy's, that have expressed disappointment (and Andy himself agrees that, at its best, the LI is capable of 'stellar shots').

Without wanting to question Andy's professionalism or Reiss' integrity I believe Andy's experience is untypical but I do not have an explanation as to why.


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## garydyke1

Send it back and have it tested by Fracino in Brum, next to a fully functioning one. Ill drive up there as an impartial taste tester ; )


----------



## Pdalowsky

This thread has got me to research this machine after having never heard of it.

It looks absolutely amazing.

My Gaggia may need an upgrade at some point


----------



## The Systemic Kid

Pdalowsky said:


> This thread has got me to research this machine after having never heard of it. It looks absolutely amazing. My Gaggia may need an upgrade at some point


Bit you will need to order a Scace too. Not cheap!


----------



## AndyS

GlennV said:


> OK. I was just going from an article on the Londinium blog "Londinium I - an open thermosiphon design" which said that it
> 
> did have a restrictor in the hot leg. The article seems to have been taken down now though, so presumably the design changed.


If one does a Google Images search under "espresso thermosiphon," Reiss's schematic drawing of the Londinium design appears near the top.

The differences between the drawing and the actual L1 installation are interesting. In the drawing (and in all the other thermosiphon drawings that come up on Google Images) the hot side of the loop exits the boiler at a higher point than the cool loop reenters. In the L1 final design, the thermosiphon supply and return lines are at the same height on the boiler. One could easily speculate on why this was done, what effect it has, and why a restrictor may have been removed in the final implementation (if in fact it was removed). But such speculation would be just that, speculation, and it would probably be unfair to the machine's designer. There are many choices and compromises that go into every espresso machine's design, and the simpler the machine (as in the L1), the more difficult and important those choices become.


----------



## AndyS

RoloD said:


> To be fair to Andy, there is an anomaly here - the group temperature should not be varying that much....
> 
> ...Without wanting to question Andy's professionalism or Reiss' integrity I believe Andy's experience is untypical but I do not have an explanation as to why.


Thank you for that fair-minded thought.

What puzzles me is why one or more of the other "86" L1 owners haven't taken the time to stick a thermocouple on their group and report the results. This would shed light on whether my experience is typical or not.

Reiss declines to disclose such information. But you other L1 owners don't need a Scace -- just strap on a thermocouple onto the group and periodically record the surface temperature.


----------



## GlennV

Maybe there's a problem with the auto-fill? If, for example, the sensor were not inserted far enough and the water level in the boiler were too high, and if that meant that the "HX" tube through the boiler were running largely in water when it was designed to run largely in steam, then the heat transfer into the thermosiphon circuit would be massively reduced.

(The reason for this is quite clever. Any part of the copper tube which is exposed to the steam inside the boiler must be very close to the boiler temperature, as otherwise steam will condense onto it and warm it up, whereas any copper with water on both sides will sit between the temperature of each body of water - in this case the boiler water and the water in the thermosiphon.)


----------



## coffeechap

AndyS said:


> Thank you for that fair-minded thought.
> 
> What puzzles me is why one or more of the other "86" L1 owners haven't taken the time to stick a thermocouple on their group and report the results. This would shed light on whether my experience is typical or not.
> 
> Reiss declines to disclose such information. But you other L1 owners don't need a Scace -- just strap on a thermocouple onto the group and periodically record the surface temperature.


I think andy most people prefer to let the taste of the shot do the talking, not everyone is obsessed about the temperature of the machine, it would appear you have a problem with yours, you have been offered a complete refund why don't you take it and put this to bed, seems like you are losing a lot of sleep over this......


----------



## garydyke1

Agreed it should be sent back, I assume the frustration is actually wanting the machine, minus the fault. Question remains it is a one-off , or if Andy ordered a replacement would he find similar issues?

Complete off topic, I couldnt hold it in any longer -

Andy your avatar looks a spit of a 1980's George Michael


----------



## RoloD

garydyke1 said:


> Complete off topic, I couldnt hold it in any longer -
> 
> Andy your avatar looks a spit of a 1980's George Michael


Now that was cruel!

(but I see what you mean)


----------



## lookseehear

coffeechap said:


> I think andy most people prefer to let the taste of the shot do the talking, not everyone is obsessed about the temperature of the machine, it would appear you have a problem with yours, you have been offered a complete refund why don't you take it and put this to bed, seems like you are losing a lot of sleep over this......


It isn't as simple as that though. Andy does like the machine and although he has said he may yet take Reiss up on his offer of a refund I'm guessing he would like to keep it if we can get to the bottom of the temperature 'issue'.

Maybe Reiss should offer a replacement free of charge rather than a refund if he believes the issue is isolated to Andy's machine. If the new machine works as described then we can all put this issue to bed.

As Andy mentioned, perhaps a shortcut would be if one of the other L1 owners could help out and measure their group temp over a few hours using a thermocouple. Again if the other owners have steady temps it would be a guide to Andy as to whether it's worth trying a replacement machine.

Edit: Looks like I cross posted with Gary but we're saying much the same thing.


----------



## Pdalowsky

The Systemic Kid said:


> Bit you will need to order a Scace too. Not cheap!


looks like im off back to google for some further education


----------



## RoloD

lookseehear said:


> As Andy mentioned, perhaps a shortcut would be if one of the other L1 owners could help out and measure their group temp over a few hours using a thermocouple. Again if the other owners have steady temps it would be a guide to Andy as to whether it's worth trying a replacement machine.


Although this is perfectly possible it is worth pointing out:

1) Steady temperature is not the aim. The temperature of the group is not necessarily the same as the temperature of the water passing through the coffee and, by its very nature, the group temperature is not designed to be constant - it diminishes through the course of the shot then recovers. I would expect, of course, that idle temperature to be relatively stable between shots.

2) Expanding on the above - this is not a straightforward system to measure. At times the group is cooling the boiler water, at other times the boiler water is heating the group. What we really want to measure is the brew water as it passes through the coffee - this is also the most difficult thing to measure, even with a Scace device, as you can't brew coffee and run the Scace at the same time.

3) If my mouth and brain tell me the coffee is consistent and the thermometer tells otherwise (or vice versa), I will believe my mouth and brain as I bought the machine to make coffee rather than generate readings. At the moment, my mouth and brain have yet to report a problem with the coffee output of the LI.

4) How do Andy's readings compare to other spring lever machines - say the Bosco or the IdroCompresso? As far as I know (please correct me if I'm wrong), people are comparing them to Scace readings of E61 machines. It could well be that lever machines don't perform as good on paper as they do in practice. Perhaps users even sacrifice an element of consistency for the particular ability lever machines have for getting the very best out of the coffee. On the other hand, lever owners could be all mad.


----------



## 4085

There is a very interesting thread going on at Home Barista on the L1..

http://www.home-barista.com/levers/owner-experience-with-londinium-i-t23770-970.html?hilit=strega

If that does not take you to the relevant part, it is page 98 about three comments down, from coffeeshark

The point of posting this is not to have a go at L1 owners, as the chap, (David) that does the review stresses that the cons do not outweigh the pro's and that the important think is what goes in the cup.


----------



## RoloD

dfk41 said:


> There is a very interesting thread going on at Home Barista on the L1..
> 
> http://www.home-barista.com/levers/owner-experience-with-londinium-i-t23770-970.html?hilit=strega


From that thread: "What really struck me the most is the consistency of the shots. I had read a lot about the L1's consistency, but I had no real idea of what it meant.... Whenever the grind setting is close to "dialed in", the shots are great. Constant, non-nervous streams from the bottomless PF. Really stunning."


----------



## The Systemic Kid

Yeah, had a quick look at Home Barista to see what folks across the pond are saying - 103 pages worth and counting! What seems to come out, as RoloD points out, is repeated reference to shot quality and consistency. Isn't this, in the end, what it's supposed to be about?


----------



## Ian_G

Is it me or is there an elephant in the room? Temperature stability. Either it makes no difference. Or it makes a huge difference. Having read "Extraordinary Delusions and the Madness of Crowds" I can see why people might get carried off on suggestion alone - it's meant to be consistent , so it is...

Thermal stability according to one set of measurements is absent. How can that equate to consistency - lets answer that question, if we can. But maybe we don't need to. How thermally stable are other competing devices, lever machines etc? Maybe they're all shot to shit. It seems we are not yet qualified to judge. But that is no reason to wish the problem away.

I'm thinking of buying the Londinium. But there is no chance if it turns out to be a lottery whether I'll get a good shot.

On the other hand respected people have favourably compared the Londinium to the best and that cannot be overlooked.

So lets get an honest discussion going to decide whether the machine is worth a toss or not.


----------



## The Systemic Kid

If I recall correctly, when Glen began an in-depth review for this forum on the LI, he measured brew temp using a thermocouple probe through the portafilter and reported that the temp was consistent around 93c. I'm surprised this hasn't been alluded to before on this thread. Or did I dream this?


----------



## garydyke1

Damn, this thread could have been resolved in 1 or pages 2 then


----------



## The Systemic Kid

Ian_G said:


> I'm thinking of buying the Londinium. But there is no chance if it turns out to be a lottery whether I'll get a good shot. On the other hand respected people have favourably compared the Londinium to the best and that cannot be overlooked. So lets get an honest discussion going to decide whether the machine is worth a toss or not.


Would that it was that simple Ian. Lever and pump pressure driven machines are chalk and cheese. The former has a long tradition traceable back to the beginnings of making espresso but whilst they were capable of delivering good to great shots, they could be inconsistent and temperamental. Pump driven machines gained in popularity because they ironed out the levers inconsistency. Now, there is a bit of resurgence in lever machines with the LI 'back to basics' approach at the forefront with the Bezzera Strega combining elements of a pumped pressure approach with a lever in a hybrid design. If you are seriously thinking of getting a lever or pump pressured machine - test them in action and see what differences you notice in shot extraction. Lever machines are capable of delivering, IMO, a wider taste profile because both pressure and temp are designed to diminish during the course of each shot extraction.


----------



## aaronb

The Systemic Kid said:


> Yeah, had a quick look at Home Barista to see what folks across the pond are saying - 103 pages worth and counting!


It's mostly espressotime trolling, not noteworthy and why I stopped participating on the L1 discussions there

(and I believe other owners too).


----------



## Ian_G

I think it's time for some cross fertilisation. It seems the yanks are as yet ignorant of the temperature stability problem. I will bring up up the problem and see how they react. In all fairness this may be an issue, it may not. But if lots of people get involved in measuring then we can get better data. And that only helps purchasing decisions. I'm sorry Reiss I'm a buyer not a seller, but it may in the end help you as well.


----------



## coffeechap

I think it's time to go to bed, for the record I love my lever and would never go back o a pump driven machine, the one thing I know is that I have NEVER pulled a better shot than the ones I get from the Bosco. If you are considering buying a lever then for goodness sake try one out instead of deliberating over figures from something that can never rationalise the pure heaven of a great tasting lever pulled shot....................


----------



## 4085

Actually, Coffeechap makes a good point. If you are considering an upgrade, why do most automatically choose E61? A lever, with or without problems can make a superb cuppa and unless you go top end E61, you are missing a trick!


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## aaronb

Good words coffeechap.

I've had my Londinium I since December and whilst I am still learning and getting to grips with it the only sink shots I've ever pulled were dialling in new beans with the grind way off, everything I've tried has been tasty and I have enjoyed immensely. I enjoy my shots more than some I've had pulled for me on e61 machines, and love the process of pulling the shot.


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## sjenner

coffeechap said:


> I think it's time to go to bed, for the record I love my lever and would never go back o a pump driven machine, the one thing I know is that I have NEVER pulled a better shot than the ones I get from the Bosco. If you are considering buying a lever then for goodness sake try one out instead of deliberating over figures from something that can never rationalise the pure heaven of a great tasting lever pulled shot....................


Indeed... Coffeechap.

You have a Bosco... Reiss's Bosco...

What's the difference between the two?

Both are hand built using good quality materials... Although, what I have seen of some of the Bosco innards...(your one coffeechap), the chassis is somewhat rudimentary, with a few sharp edges and bits of old iron... (I'm not intending to be rude, you'll see where I am going)... The Bosco is aimed at commercial situations, so it has around a 6l boiler, it has a drain... Overall a very good machine.

The difference between it and the L1 are relatively minor, perhaps the L1 is built a bit better... Fracino is a large operation, Bosco is a little workshop in Naples, run by a Mr. er... Bosco! So manufacturing standards should be higher.

The big difference though, is the price... The Bosco is nearly £3000, whilst the Londinium which is cheaper to run and aimed at the "home-barista", is £1500... Half the price!

I wonder if the L1 had been announced in November with a price tag of (say) £2500, would there be discussions like this going on? I doubt it, nobody is droning on and on about the Bosco, or the Cremina, or best of all the Idrocompresso (all £11000 of it).

Perhaps by having a bloke like Reiss around, providing top quality gear at rock-bottom prices (relatively), that people think that it's a bargain...

...*There must be something wrong with it!*

Now coffeechap, if that Bosco had been £3000, would you have bought it?

Personally, I think I have picked up a work of art, it is beautiful and the coffee is better than I have ever been used to... and what's more I have got a bargain, and a really good bloke to help me out when I get baffled by something.









BTW: I have just looked on HB at the pictures of Stephen's (fotondrv) L1, it clearly shows the hot pipe above the cold pipe on entry/exit to/from the group. http://www.home-barista.com/levers/londinium-videos-photos-by-owners-t24207.html


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## 4085

But without trying to continue this discussion when it looks like it is veering off track, if I recall, it started because someone could not verify themselves, some of the claims that were made by Londinium, and it would appear, have not yet been proven by Londinium. Surely either one side or the other can come out on top in this. If Londinium are making claims, then you would expect them to be able to back them up with data, and not written argument.

Even though I no longer have one, I would not knock the principle of the machine. It made good coffee, looked nice and ticked my boxes. that is not say it was not without issue, but hey, it is early days still. It is cheaper than a Bosco for sure, but it is also aimed at a different market. The Bosco seems to be a proven contender within the commercial marketplace whilst the L1 is still trying to gain a foothold in the domestic marketplace.........hardly a fair comparison.


----------



## painty

The Systemic Kid said:


> For what it's worth, came across this, Anyway, we were surprised at how slowly our brand new Scace meter responded to changes in temperature. It took around ten seconds to register the actual water temperature coming through the system (C-A). The Scace then continued to read brew temperature for 3-4 seconds after the water flow was shut off completely.


That's interesting, I always thought the only way to get a reasonable temperature response in the portafilter is with a fine-gauge exposed junction thermocouple; a sheathed thermocouple has a lot of thermal inertia. But then an exposed junction wouldn't last a week in the work of a portafilter device...



dfk41 said:


> But without trying to continue this discussion when it looks like it is veering off track, if I recall, it started because someone could not verify themselves, some of the claims that were made by Londinium, and it would appear, have not yet been proven by Londinium. Surely either one side or the other can come out on top in this. If Londinium are making claims, then you would expect them to be able to back them up with data, and not written argument.


Just guessing, but perhaps the designer is unhappy that this problem has been aired here rather than directly with the company in the first instance, and does not want to be drawn into some unsatisfactory trial by public forum which could tarnish the product's reputation from a one-off spurious fault or indeed something that might not relate to the product at all, who knows yet.

I know AndyS has a solid reputation in coffee machine R&D going back a decade and more, and this has traditionally been the way these kinds of issues have been discussed, so perhaps it's a bit of a culture-clash in that respect. In the absence of manufacturers data, it would be good if some LI owners could replicate Andy's observations as he asked in the original post, so it could be determined whether it is an isolated problem. But the demographic for LI owners probably doesn't include many who tinker with thermocouples and dataloggers. Which brings us to the stalemate in which the thread is now languishing...


----------



## coffeechap

Oh now you have taken the gloves off!!

I only mentioned the Bosco which indeed I bought of reiss because I love what a lever machine does, I really liked the pontevecchio lusso that I had and the la pavoni that I still have, I guess I have become smitten by lever machines.

The Bosco is built like a tank, albeit with a stainless steel boiler and associated components on the ugly inside of the machine, it is rough around the edges on the inside and is very very simple, it does indeed have a 6 litre boiler, which I am sure costs a fortune to run!! But it also has lovely finishes on the outside like gold plated panel framing and steam activated cup warmer ( I don't think the L1 even has a cup warmer, but correct me if I am wrong). In fact the Bosco was Reiss's inspiration for producing the L1. I am also sure there was a reason that Kees van der western visited Bosco when developing his idrocompresso !

But let me draw you back to your point that you made, I did not pay £3000 for my Bosco, nor did I pay the cost of the basic L1 for my Bosco infant I paid half of the price of the L1 for my Bosco.........

Would I pay £3500 for one which has the gold detailing and cup warmer, not on your nelly!! But then would I pay £1800 for the L1? ..... No I would not as I bought a proven commercial one group machine, exceptionally highly regarded in the industry which purports to be exactly what it is a quality commercial one group lever, I bought it off the back of a lot of research and recommendations, but I bought it because I desperately wanted a fabulous lever machine that produced fabulous espresso for less than a grand! Which is exactly what I got, I had no other expectations of my machine and no other criteria, it was based on price and boy was I LUUUUUUCKY.

The fact it was bought from reiss is irrelevant as when I went to pick up the BOSCO I clapped eyes on the beautiful little L1, even played with it for hours, Reiss gave me all the time in the day to explain my machine and was quite rightly proud of the machine that he had put together and I was genuinely amazed at the compact design and functionality of the L1.

Anyway, like I said before my time on this thread is at an end clearly someone is unhappy about an element of their machine that is causing them reason for concern, not one of my issues nor would it be if I had purchased an L1 as the biggest thing for me (apart from the price) is getting a shot of wonderful espresso and enjoying the amazing cafe latte that I have in the morning of having a huge smile on my face every time I draw down that amazing lever............


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## lookseehear

I don't know why this thread has veered back onto the track of whether you can make great espresso on an L1 - clearly that many people can't be wrong - it's a great machine to be sure! No one is arguing with that (unless I've missed something).

The thread was started because someone took some measurements which didn't seem to add up to claims made in marketing material for the machine.

Clearly there are only three possible reasons for this:

1 - the measurements are wrong

2 - there is something wrong with Andy's machine

3 - the machine isn't as stable as was originally claimed by Reiss

1 is unlikely - attaching a thermocouple and a data logger to the outside of the group is not complicated and 7kg of brass is unlikely to be destabilised significantly by 60ish ml of water. By this I'm getting at the fact that I find it hard to believe that the water as it passes through the coffee will not be at a temperature related to the temperature of the group.

2 seems very possible (as his machine has a leaky valve at certain pressurestat settings) and Reiss has made it very clear he believes this problem is isolated to one machine. The sad thing is he hasn't been offered a replacement which is surprising as he has followed the instructions provided by Reiss and that hasn't sorted it out. Another option is for another Londinium owner to take some pretty simple measurements to check whether theirs is the same or not but none of the owners reading this thread have offered to do this sadly.

3 is a possibility (but we would all prefer it to be 2). I would genuinely love to see some evidence that this isn't true but currently Andy's measurements are the only thing we have to go on. It also seems a bit unlikely that the only customer who is taking measurements happens to have received an atypical machine.

It would be great to see this cleared up one way or the other though!


----------



## lookseehear

painty said:


> That's interesting, I always thought the only way to get a reasonable temperature response in the portafilter is with a fine-gauge exposed junction thermocouple; a sheathed thermocouple has a lot of thermal inertia. But then an exposed junction wouldn't last a week in the work of a portafilter device...
> 
> Just guessing, but perhaps the designer is unhappy that this problem has been aired here rather than directly with the company in the first instance, and does not want to be drawn into some unsatisfactory trial by public forum which could tarnish the product's reputation from a one-off spurious fault or indeed something that might not relate to the product at all, who knows yet.
> 
> I know AndyS has a solid reputation in coffee machine R&D going back a decade and more, and this has traditionally been the way these kinds of issues have been discussed, so perhaps it's a bit of a culture-clash in that respect. In the absence of manufacturers data, it would be good if some LI owners could replicate Andy's observations as he asked in the original post, so it could be determined whether it is an isolated problem. But the demographic for LI owners probably doesn't include many who tinker with thermocouples and dataloggers. Which brings us to the stalemate in which the thread is now languishing...


Hit the nail on the head there!


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## sjenner

dfk41 said:


> But without trying to continue this discussion when it looks like it is veering off track, if I recall, it started because someone could not verify themselves, some of the claims that were made by Londinium, and it would appear, have not yet been proven by Londinium. Surely either one side or the other can come out on top in this. If Londinium are making claims, then you would expect them to be able to back them up with data, and not written argument.
> 
> Even though I no longer have one, I would not knock the principle of the machine. It made good coffee, looked nice and ticked my boxes. that is not say it was not without issue, but hey, it is early days still. It is cheaper than a Bosco for sure, but it is also aimed at a different market. The Bosco seems to be a proven contender within the commercial marketplace whilst the L1 is still trying to gain a foothold in the domestic marketplace.........hardly a fair comparison.


No DFK, this is about digital vs analogue I reckon.

We humans have mastered the art of both but we can't usefully measure the latter...

....We can't take the statement "this machine makes excellent coffee and I wouldn't trade it", and feed it into a computer to give us a spreadsheet or something. AndyS can with his digital equipment, which he is using to measure an analogue machine...

...So where does this leave us?

Well more than 80 users report a heavenly experience







and one user states that there is something wrong, but nevertheless likes the coffee, oh and he also has an involvement in a product which has been criticised here... or rather not criticised but questioned... Namely the VST basket.

...There are another couple of factors here as well. Firstly, we don't know whether the somewhat variable figures that AndyS produced are either accurate or typical, and secondly we don't know whether this is the way that the group and thermosysphon are doing what they are supposed to and that the variability that AndyS has documented is the L1 doing it's thing, or whether Andy's machine is faulty... perhaps a problematic safety valve that cuts in early.?

As for my comparison to the Bosco, that is not an unfair comparison, there are some very important commonalities, the same goes for the Quickmill, and the Idrocompresso. The important difference is the price.


----------



## 4085

Ok, let us widen this a bit further then. The L1 might be on paper, a fantastic machine, but because of the business model followed, it has largely been brought to the market as an untested commodity. this means that the early purchasers are really nowt more but guinea pigs. that is fine, because the item is not advertised to the general public. It has been carefully brought to the attention of lever fanatics on forums, where the hope is that design flaws etc etc can be worked on on the fly.

Quite simply, if you had gone to Harrods and bought your L1, REGARDLESS of the price point, and it had had the issues that the L1 has suffered, you would take it back. Do, it is not the finished article but a work in progress. I am guessing that there are 100 or so units around the world. Most pwners will be happy to be in so early, but it does not alter the fact that from day one, the L1 has been plagued with transit problems causing internal and external damage, issues of serious flexing on some models and the list goes on....but, it still does make good coffee!


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## coffeechap

sjenner said:


> No DFK,
> 
> As for my comparison to the Bosco, that is not an unfair comparison, there are some very important commonalities, the same goes for the Quickmill, and the Idrocompresso. The important difference is the price.


Actually you compared the bosco with reference to cost and as such is an invalid argument here as I am a purchaser of a second hand machine, at half the cost of a new L1, perhaps an owner of a new bosco could comment on the value principles, they are also very different machines in design all be it with the same group.

Regardless of the involvement of the publisher with other products, which I believe he himself gets particularly defensive about, the fact remains there is a perceived issue with his machine which judging by the other completely satisfied customers who may or may not be interested in the science of temperature, appears to be an anomaly. Therefore the options available to him are

A) return the machine for a complete refund as per the manufacturers suggestion and thereby meeting the legislative requirements of a seller

B) keep the machine and attempt to iron out his issues, perhaps as he is experienced in modifications he could improve the L1, he has after all felt it necessary to improve nearly all of his past equipment.

C) send it back to exchange for another one, although reiss is not legally obliged to do this.

If anything this debate has served to put the cat among the pigeons and has probably served as a reminder to most L1 users as to their original reason for purchasing an L1 and that was beauty simplisity and taste of resultant shot.

Luke you really would benefit from going to reiss and actually trying the l1 out as espresso is not after all just about scace machines and science. Perhaps you could make a decision as to whether you think it meets your requirements then.

It would also be nice at some point for the temperature debate to be resolved however I don't see it happening anytime soon without cooperation.


----------



## ronsil

Please don't let this disintegrate into something no one wants. I have horrible recollections of something happening on another forum where a prominent member attacked Versalab over some technical problem & it became so personal the thread had to be locked down. In a similar situation he was offered a replacement machine which he never took up but continued to criticize Versalab.

I like smooth running equipment but am not obsessed with the technicalities. My criteria are completely controlled by the final result in a cup. Is it to my taste & did I enjoy making it. If something is happening to prevent this, is the Company(s) doing all they can to put the matter right.


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## Ian_G

The debate on temperature profile on Home Barista has produced a graph, as I thought it might, that shows a stable temperature profile. This seems to show that Reiss is right and Andy has a faulty machine.


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## sjenner

dfk41 said:


> Ok, let us widen this a bit further then. The L1 might be on paper, a fantastic machine, but because of the business model followed, it has largely been brought to the market as an untested commodity. this means that the early purchasers are really nowt more but guinea pigs. that is fine, because the item is not advertised to the general public. It has been carefully brought to the attention of lever fanatics on forums, where the hope is that design flaws etc etc can be worked on on the fly.
> 
> Quite simply, if you had gone to Harrods and bought your L1, REGARDLESS of the price point, and it had had the issues that the L1 has suffered, you would take it back. Do, it is not the finished article but a work in progress. I am guessing that there are 100 or so units around the world. Most pwners will be happy to be in so early, but it does not alter the fact that from day one, the L1 has been plagued with transit problems causing internal and external damage, issues of serious flexing on some models and the list goes on....but, it still does make good coffee!


What "issues"?

I have no issues with my Londinium.


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## 4085

Stephen, correct me if I am wrong but I do no think I said that you had issues. I said, and say again, that other L1 owners around the world, have had issues with their machines (read the international forums). Whether this has been opened up to forum members around the world for public debate or not, is irrelevant. Please correct me if I am wrong again, because my memory sometimes plays me up, but was it not you who had an 'issue' with your L1 and plumbing upon arrival, and Reiss immediately care round and sorted it out, or was that another person and it was not an issue, but the sort of thing us pioneers expect when buying new kit?


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## sjenner

coffeechap said:


> Actually you compared the bosco with reference to cost and as such is an invalid argument here as I am a purchaser of a second hand machine, at half the cost of a new L1, perhaps an owner of a new bosco could comment on the value principles, they are also very different machines in design all be it with the same group.
> 
> Regardless of the involvement of the publisher with other products, which I believe he himself gets particularly defensive about, the fact remains there is a perceived issue with his machine which judging by the other completely satisfied customers who may or may not be interested in the science of temperature, appears to be an anomaly. Therefore the options available to him are
> 
> A) return the machine for a complete refund as per the manufacturers suggestion and thereby meeting the legislative requirements of a seller
> 
> B) keep the machine and attempt to iron out his issues, perhaps as he is experienced in modifications he could improve the L1, he has after all felt it necessary to improve nearly all of his past equipment.
> 
> C) send it back to exchange for another one, although reiss is not legally obliged to do this.
> 
> If anything this debate has served to put the cat among the pigeons and has probably served as a reminder to most L1 users as to their original reason for purchasing an L1 and that was beauty simplisity and taste of resultant shot.
> 
> Luke you really would benefit from going to reiss and actually trying the l1 out as espresso is not after all just about scace machines and science. Perhaps you could make a decision as to whether you think it meets your requirements then.
> 
> It would also be nice at some point for the temperature debate to be resolved however I don't see it happening anytime soon without cooperation.


Sorry coffeechap but I think you just missed my point...

I was attempting to point out that the dichotomy is about the comparatively low price, and I have given similar examples... If you want to get pernickety, then the Quickmill is almost the same, particularly in terms of the thermosyphon. That is nearly £3000, just like the Bosco. Apart from the fact that most people who post about the Quickmill, have made changes to their machine as soon as they have received it. The only L1 user who has made such changes (i.e. functional, as opposed to decorative) is AndyS, ostensibly to cure a fault?

There is no debate amongst the owners that just like coffee that the Londinium produces.


----------



## RoloD

dfk41 said:


> . The L1 might be on paper, a fantastic machine, but because of the business model followed, it has largely been brought to the market as an untested commodity. this means that the early purchasers are really nowt more but guinea pigs. that is fine, because the item is not advertised to the general public. It has been carefully brought to the attention of lever fanatics on forums, where the hope is that design flaws etc etc can be worked on on the fly.
> 
> Quite simply, if you had gone to Harrods and bought your L1, REGARDLESS of the price point, and it had had the issues that the L1 has suffered, you would take it back. Do, it is not the finished article but a work in progress. I am guessing that there are 100 or so units around the world. Most owners will be happy to be in so early, but it does not alter the fact that from day one, the L1 has been plagued with transit problems causing internal and external damage, issues of serious flexing on some models and the list goes on....but, it still does make good coffee!


 I'm sorry, this is simply not true and such comments make me very angry. I have the very first LI Standard model and it works perfectly. The only modifications made (as far as I know) since then have been to stand up to heavy abuse in transit. The LI has not been 'plagued with transport problems', simply that some couriers were dropping the machine from a great height and causing damage - the machines and packaging have since been redesigned to cope with such abuse. Flexing is a non-issue. Compared to what importers have had to do from other level machines from well known Italian manufacturers (basically, completely rebuild them) the LI is at an advanced stage of production. The build quality is very high. This is not a 'work in progress'.

Yes, there have been teething problems but they have been minor and Reiss has gone out of his way to fix them. There are machines that have been made for decades that have ten times the quality problems of the LI. Because Reiss is so accessible and has been made the design process very open, any problems have been very apparent - very few machines coud the survive the sort of scrutiny the LI has been put under without users finding some small faults. The vast majority of machines have NOT had problems, and those that did were almost all caused by damage in transit. Quality control is, I believe, much higher than most Italian models.

There does seem to be an element in these forums wanting to find fault with the LI. Perhaps it is because of Reiss' slightly abrasive online personna (in person he is absolutely charming), I don't know. The user feedback has, with only a couple of exceptions, been not merely positive but ecstatic. Even the most critical user admits it is great value for money and can make fantastic espresso. This is NOT a work in progress.


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## sjenner

dfk41 said:


> Stephen, correct me if I am wrong but I do no think I said that you had issues. I said, and say again, that other L1 owners around the world, have had issues with their machines (read the international forums). Whether this has been opened up to forum members around the world for public debate or not, is irrelevant. Please correct me if I am wrong again, because my memory sometimes plays me up, but was it not you who had an 'issue' with your L1 and plumbing upon arrival, and Reiss immediately care round and sorted it out, or was that another person and it was not an issue, but the sort of thing us pioneers expect when buying new kit?


That is true... However, this was due to a shipping problem... In no way, as I explained would that (as I pointed out at the time) either have been noticed by me, the "leak" was so small that the output evaporated immediately. Reiss did not come round to fix my machine, he came round because...

1: It was the first Londinium in the wild (actually delivered about six miles from his home) and Reiss was excited to examine the packaging, and see the product being used in its place. He came round a second time to make the repair.

2: If that machine had not been seen by Reiss, it would still be leaking, and it would not be affecting in any way the coffee that the machine produced.

3: It was the beginning for Reiss of a quest to defeat the incredible capacity that couriers have for destroying that which they are supposed to be carrying safely.

Most (if not all) of the problems that I have read about have been caused by shipping damage, and I would expect people to be a little disappointed. You implied that I had plumbing problems... This not so... I have had problems with water quality, but then I live in south east London, where the water comes out of the tap with visible lumps of chalk suspended in it, along with God knows what else???


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## sjenner

ronsil said:


> Please don't let this disintegrate into something no one wants. I have horrible recollections of something happening on another forum where a prominent member attacked Versalab over some technical problem & it became so personal the thread had to be locked down. In a similar situation he was offered a replacement machine which he never took up but continued to criticize Versalab.
> 
> I like smooth running equipment but am not obsessed with the technicalities. My criteria are completely controlled by the final result in a cup. Is it to my taste & did I enjoy making it. If something is happening to prevent this, is the Company(s) doing all they can to put the matter right.


BTW Ron: I don't think I have ever thanked you for pointing me towards the Londinium website, when I posted as fivethirty on HB and asked about the machines that I had narrowed down to (Spaziale or Strega?)...

So, thanks very much, you did me a huge good turn.


----------



## coffeechap

sjenner said:


> Sorry coffeechap but I think you just missed my point...
> 
> I was attempting to point out that the dichotomy is about the comparatively low price, and I have given similar examples... If you want to get pernickety, then the Quickmill is almost the same, particularly in terms of the thermosyphon. That is nearly £3000, just like the Bosco. Apart from the fact that most people who post about the Quickmill, have made changes to their machine as soon as they have received it. The only L1 user who has made such changes (i.e. functional, as opposed to decorative) is AndyS, ostensibly to cure a fault?
> 
> There is no debate amongst the owners that just like coffee that the Londinium produces.


I don't believe I was being pernickity, you made direct reference to MY bosco not a new one which you have clearly seen and poked about in at some point. Thus it is important at that juncture to emphasise the cost of that machine when purchased by me which was less than half the price of your L1. You also asked if I would purchase a bosco at 3000 to which I said no but I also highlighted the fact that (although comparatively cheap) I would also not buy the L1 as it did not meet my sub £1000 criteria nor will it at ant point in the near future as they are not available used yet.

Is the bosco worth it at the price I paid? absolutely as the group alone is worth that.


----------



## sjenner

coffeechap said:


> I don't believe I was being pernickity, you made direct reference to MY bosco not a new one which you have clearly seen and poked about in at some point. Thus it is important at that juncture to emphasise the cost of that machine when purchased by me which was less than half the price of your L1. You also asked if I would purchase a bosco at 3000 to which I said no but I also highlighted the fact that (although comparatively cheap) I would also not buy the L1 as it did not meet my sub £1000 criteria nor will it at ant point in the near future as they are not available used yet.
> 
> Is the bosco worth it at the price I paid? absolutely as the group alone is worth that.


I have not "poked around" in your Bosco, what I saw, was it being lovingly cleaned and the seals being replaced in order for it being prepared to be sold. At that time, I also saw some constructional detail, that in my view would be entirely predictable bearing mind where it was made... A tiny workshop in Naples...! as opposed to a purpose built factory equipped with laser tools etc... these were not critical of the functioning of the machine, I have never tasted so much as a drop of coffee from it, but Reiss told me that it was stupendous. And yes, you did get an astounding bargain, I was watching it on Ebay, but I was in no position to bid bearing in mind that I had just received my Londinium and paid for my HG One.

If that Bosco had been £3000, there would be NO people on these forums (particularly posters that have been banned from other fora) criticising that functioning.

IanG made a comment on HB, in fact he opened a topic, and apart from the graph that he mentioned above... The commenters were somewhat scathing of AndyS.


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## Glenn

I would like to bring this thread to a natural close (without locking it of course)

There will always be critics of any machine, at any price point

As with any brewing methods, taste should be the most important indicator - and this is purely a personal method of evaluation.

I would encourage anyone to try a machine and get hands-on time where possible, before making purchasing decisions if they are undecided.

Having had the pleasure of an Londinium I on my bench for a number of weeks I can see myself purchasing one in the future as I didn't want to give it back. The espresso I was enjoying was some of the best I had consumed in recent years.


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## coffeechap

Ps I don't see poking around as in anyway provocative it is just what people do when they look at machines


----------



## The Systemic Kid

Glenn said:


> I would like to bring this thread to a natural close (without locking it of course)


I don't think it's necessary to bring the thread to a close, Glen. Healthy debate and enquiry are surely to be welcomed. Andy has put some data in the public domain regarding his experience with the LI and extrapolated some perfectly reasonable questions. From an investigative perspective, as Andy says, it would be interesting to see if his data can be replicated with other LIs or if his experience is isolated. Unfortunately, the thread has become, at times, a little heated and veered off topic which is a shame. I think the subjective commentary in this thread on the LI's capability to produce shot extraction of the highest quality has been sufficiently repeated. What the thread should confine itself to is more neutrally observed replicable data to illustrate the LI's temperature stability or otherwise.


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## coffeechap

Might also be an idea to move it to the lever section so other threads within this category don't get overlooked.


----------



## vikingboy

Maybe I'm missing something here but it sounds like the OP machine was suffering from some fault which was resolved by reducing boiler pressure and therefore stalling the basic system which controls the temperature - hence the two groups of data.

doesnt this invalidate the whole test and shouldn't the OP resove the original issue before reporting data?


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## AndyS

painty said:


> Just guessing, but perhaps the designer is unhappy that this problem has been aired here rather than directly with the company in the first instance, and does not want to be drawn into some unsatisfactory trial by public forum which could tarnish the product's reputation from a one-off spurious fault or indeed something that might not relate to the product at all, who knows yet.


Just for the record, Reiss and I had a lively exchange of emails (at least 18 by my count) leading up to me placing an order, receiving the machine, and reporting the leaky safety valve.

I first brought up the temperature variation issue in an email to him on 3/17. He didn't respond to that, which seemed out of character, so I sent it again on 3/19. After again receiving no response, I sent him a private message through this forum on 3/25. It also went unanswered.

So I get your point that Reiss may be unhappy to see this topic out in public, but if you were in my position, having bought a brand new machine and being more than 5000 km away from London, what would you have done?


----------



## 4085

Roland, why on earth should this make you angry? We are supposed to be on a Forum, discussing a number of topics. No sentiment should be brought into any discussion. It is strange though. I see your name cropping up on forums around the world, where someone has so something bad to say about Londinium and you seem to come out of your corner fighting for the good name, as you do here. You have suggested that there are not problems with the L1...I beg to differ. Currently there is a German gentleman named Coffeshark who has posted a very comprehensive and perhaps un-arguable with review of his machine, which includes despite the fix to the anti=vac, his machine still arriving soaking wet. The group arrived without any lubrication to it. The lid is badly bent on the top left front as you look at it, yet without evidence to damage to packaging....but despite this, it still makes good coffee!

The machines have issues, but that is not to say there are still not very good machines. They are priced at the top end of most peoples budget for a domestic machine, and therefore I think the consumer is right to expect a certain level of finesse. The machine was designed very well, but not road tested. Of course there was a prototype but no consumer testing, which means as niggles, faults, call them what you will appear, they are dealt with.

Explain then why there has been an unnanounced change to the chassis where the drip tray connects, having changed from 3 bolts to welding. If this was not needed, then why do it. that suggests to me, whether I am being harsh or not, that the machine is a work in progress. Quality control issues clearly exist at the manufacturing end of things but sadly, these reflect on the name on the machine, not the manufacturer.

I hope all these issues, defects, non-issues etc become resolved, but until they do, then there are going to be gripes from people around the world.

Look, the bottom line is this. If I ask you to visit my house for a cup of coffee, and ask you how it is, I expect you to say nice whether it is or is not. If I ask you round to my cafe and sell you a cup of coffee, then no matter what I and my supporters think I am left open to critical acclaim.

This is the link to coffeeshark. It is page 38, 3 threads down. Read it!

http://www.home-barista.com/levers/owner-experience-with-londinium-i-t23770-970.html?hilit=strega


----------



## rodabod

It looks like a number of machines took a bit of a battering on the post judging by the number of owners reporting damaged drip trays, etc. It doesn't seem unreasonable that user AndyS' machine could have been damaged in some way too.

While we can only speculate on the buyer's exchanges with the company, I thought it would look best on the company's part if they would provide some sort of service to rectify the situation. International shipping must only be a few hundred Pounds there and back, and that could easily be less than the resultant cost in drop of sales due to potential buyers being put off by reading about unhappy owners.

I'm probably being cynical, but I hope the suggestion of closing this thread wasn't due to the forum having a commercial interest in keeping Londinium looking favourable, given that they are forum advertisers.


----------



## forzajuve

A few points on this thread from a neutral observer who is looking at options for an upgrade including the L1 in the future:

A) it seems clear that no one else on this forum has an issue with temp stability on their L1, to the point at which they have looked to question it with specific measurements.

B) I cannot speak for other forums as I wouldn't waste my time there (CFUK is the king) but it seems that equally no similar issues have been raised.

C) the OP clearly feels there is a problem and has investigated with direct measurements that support his query, but without any other data to compare it is not clear whether it is an isolated case or not.

D) given the strength of the response by other L1 owners I am minded to think this is a one off and as such and exchange or refund should be sought unless othe data can confirm/deny the OP findings.

E) some people will always look on numbers with disdain but to assist the OP it would have been good to have someone step up with other readings to but his mind at rest to whether it was isolated or not.

From my own point of view I would say this hasn't changed my opinion on the machine which seems to be much loved by many.


----------



## Glenn

Not in any way rodabod

The thread was veering off track.

We have a neutral stance and no commercial interest as we are not resellers of any of the products featured by our advertisers.


----------



## AndyS

GlennV said:


> Maybe there's a problem with the auto-fill? If, for example, the sensor were not inserted far enough and the water level in the boiler were too high, and if that meant that the "HX" tube through the boiler were running largely in water when it was designed to run largely in steam, then the heat transfer into the thermosiphon circuit would be massively reduced.
> 
> (The reason for this is quite clever. Any part of the copper tube which is exposed to the steam inside the boiler must be very close to the boiler temperature, as otherwise steam will condense onto it and warm it up, whereas any copper with water on both sides will sit between the temperature of each body of water - in this case the boiler water and the water in the thermosiphon.)


Glenn, that is very interesting and at some point I will experiment with the sensor position. Out of curiosity, can you estimate how much faster is the heat transfer is from steam to copper rather than water to copper? Obviously, steam at 120C has greater heat content per gram but water is so much denser.


----------



## dpiette

Here is a post on HB where Eric S measures the warm-up temps on an L1.

Eric gives permission to repost the chart with acknowledgement, so here it is, credit Eric Svendson:









Now, as is mentioned in the HB thread, Eric is not measuring the exact thing that Andy is. But I have not seen any other charts of L-1 temps

(edited a typo)


----------



## RoloD

dfk41 said:


> Roland, why on earth should this make you angry?


 Simply because I think you have distorted the facts to say that the LI is a work in progress, when almost all the problems are to do with damage in transit which Reiss has done his best to fix. There are various teething problems but that is very different to say it is a work in progress or that customers are guinea pigs. In terms of operation and function the first machine (which I have) and the latest machine are, as far as I know, the same. The only significant change is a bracket added to secure the boiler in transit.


> We are supposed to be on a Forum, discussing a number of topics. No sentiment should be brought into any discussion. It is strange though. I see your name cropping up on forums around the world, where someone has so something bad to say about Londinium and you seem to come out of your corner fighting for the good name, as you do here.


Forums around the world? I've commented on H-B too; I don't know what is 'strange' about that and I am not sure what you are implying. I don't work for Londinium (apart from once shooting a promotional video for Reiss), I only know Reiss because I bought a grinder off him and he helped me set up my Cremina. If I had something bad to say about the machine, I'd say it. I bought the machine (it was the same one Glenn had on trial) simpy because I was impressed with it.

I suppose I have a lot of sympathy for Reiss because he has been so open in the development of the machine and so helpful to all his customers, that to say the LI is a 'work in progress' is simply unfair and doesn't reflect the reality. For a very small company like Londinium, such comments can have a huge impact.

I've never said there have been no problems with the LI, but the issues are minor - some from the Italian manufacturer of the group, one or two Fracino quality control issues, and a fair amount of damage in transit. Hardly any of these issues have impacted on the functioning of the machine.



> Explain then why there has been an unnanounced change to the chassis where the drip tray connects, having changed from 3 bolts to welding. If this was not needed, then why do it.


I have no idea. Presumably it is something to do with efficiency in the manufacturing process. Either way, it has no impact on the functioning of the machine; it is a non issue (for what it's worth, my machine is welded rather than bolted) and you would find similar examples in any small run custom manufactured product where small changes are made continuously. This is not the case with mass produced products where, after many prototypes, identical items are made by the thousand.


> This is the link to coffeeshark. It is page 38, 3 threads down. Read it!
> 
> http://www.home-barista.com/levers/owner-experience-with-londinium-i-t23770-970.html?hilit=strega


Yes, I had read that. (His summary: Overall, the L1 is an outstanding machine with a number of minor flaws and cosmetic blemish. The consistency of the shots, the result in the cup and the steaming performance are beyond anything I have ever experienced).There was a problem with the case sides on this machine and he didn't like the quality of the plating on the group. The former was a quality control issue with this particular machine, the latter really goes back to the Italian manufacturer of the group and, like so many Italian manufacturers, their finish isn't perfect. There were also some damage in transit. Overall he was extremely happy with the machine. This is NOT a case of work in progress.


----------



## AndyS

RoloD said:


> Steady temperature is not the aim. The temperature of the group is not necessarily the same as the temperature of the water passing through the coffee and, by its very nature, the group temperature is not designed to be constant - it diminishes through the course of the shot then recovers. I would expect, of course, that idle temperature to be relatively stable between shots.


Agree 100%. The point of the very first graph posted in this thread was that the *range* of brew temperatures delivered by the machine for any particular shot was directly related to the starting group temperature. But your last sentence is important: the idle (starting) temperature should be as stable as possible. I believe the taste variation in the shots due to temperature variation *in my machine* is easily discernible, but as previously stated I am not tasting blind. Even so, there are hundreds of espresso taste-vs-temperature reports going back at least a decade, and it would be astonishing if the commonly perceived difference between an average 205F (96C) shot and an average 190F (88C) shot were due simply to power of suggestion or some kind of mass hysteria.



RoloD said:


> this is not a straightforward system to measure. At times the group is cooling the boiler water, at other times the boiler water is heating the group. What we really want to measure is the brew water as it passes through the coffee - this is also the most difficult thing to measure, even with a Scace device, as you can't brew coffee and run the Scace at the same time.


The Scace is not a perfect measure. It is a *modelling* device, and can only *simulate* what goes on during an actual extraction. Experience has shown, however, that it is durable, objective and reasonably accurate. It was not accepted by the World Coffee Event group because Greg Scace is a clever salesman or has lots of influential friends; it was accepted because it produces repeatable results that correlate well with the subjective impressions of experienced coffee tasters.



RoloD said:


> If my mouth and brain tell me the coffee is consistent and the thermometer tells otherwise (or vice versa), I will believe my mouth and brain as I bought the machine to make coffee rather than generate readings. At the moment, my mouth and brain have yet to report a problem with the coffee output of the LI.


I don't argue with your logic or your subjective impressions. I simply ask that you accept my logic: just because you and many others report that their L1's are operating well, that doesn't imply (1) mine is operating well, or (2) I have undisclosed ulterior motives, or (3) I am incompetent.


----------



## 4085

Roland, I have not distorted anything at all. If the L1 is not a work in progress, then what is it? There are issues widely related that you chose to ignore or forget about. for example, I mentioned several issues with coffeeshark's machine and you reply on two, which are not Londiniums fault, that is the side allegedly damaged somewhere and the crap finish on the Italian group. What about the valve issue to keep the machine dry and the lack of any lube on the group.

You are obviously aware of other issues as you have posted, here for example when someone videos their machine flexing, and immediately you reply;

Postby RoloD on Apr 01, 2013, 10:25 am

Certainly my Londinium I IS rock solid - there does seem to be something wrong with the machine in that video. It looks to me like the chassis is moving in relation to the side panels rather than the chassis itself flexing.

I would, however, suggest removing the flower pot modification.

RoloD

Sorry, probably me being odd again. Anyway, despite appearances, I am not an embittered ex L! owner seeking retribution via forums. I also had a first release HG One, and after a week binned it. It was just not for me, but have you seen me comment on or try to dissuade any others from buying one? I would not stop any L1 owner from buying one, but I feel quite able to justify any criticism or praise I choose to pass without the continual holier than though stance taken by some on here!

I often ask myself, would I have another L1 and presuming one or two things could be sorted the answer would be yes, although it is very unlikely of course. So, I hope you and all the other L1 owners and prospective owners enjoy their machines. To anyone thinking of buying one, remember to check out the Strega as an alternative. I am bowing out of this thread now. I have said what I want to. I will still read it though as I would like to see what the outcome eventually is.

And a last point Roland, why not see if you can find out the reasoning behind the change to the chassis blots/welds. A lot of out HB friends think they know why, especially Mr Flower Pot who you already know!


----------



## AndyS

The Systemic Kid said:


> For what it's worth, came across this, Anyway, we were surprised at how slowly our brand new Scace meter responded to changes in temperature. It took around ten seconds to register the actual water temperature coming through the system (C-A). The Scace then continued to read brew temperature for 3-4 seconds after the water flow was shut off completely. We experienced this over numerous tests, at different brew temperature settings. . Full entry here:
> 
> http://www.slayerespresso.com/2008/06/14/accounting-for-total-brew-temperature-stability/#more-150


Thank you for pointing out that post, but IMHO it is simply not credible. The Scace Device uses a 1/16" sheathed thermocouple, which has a much faster response time than the Slayer graph indicates. (Checking here and making some calculations indicates that the Scace should be within a fraction of a degree F in 2 or 3 seconds).

In addition, I am very skeptical that the Slayer flat line temperature performance is as perfect as the graph indicates. However that is really OT here.

[disclosure: I own a Scace Device and Greg Scace is a personal friend. However, we have no common financial interest or business relationship.]


----------



## RoloD

OK, David, I will bow out of this thread now too. As far as I'm concerned, a series of teething problems, mostly do with problems with transit damage or parts supplied from another manufacturer and largely cosmetic, do not add up to a 'work in progress'. To an extent, all machines manufactured on this small scale will always be a 'work in progress' as they will be continually improved. Despite these small issues, users seem to be unanimous in saying that the build quality is very high. Other manufacturers should delight in the fact their machines have not been put through the same level of scrutiny (many would fall at the first post).

Andy - I hope you don't think I have implied you are incompetent or have 'undisclosed ulterior motives' and I accept your logic. I have no favoured explanation for the apparent anomalies.


----------



## mathof

A poster on HB has strapped a thermocouple on the group of his L1. He reported a moment ago: "After the machine heated the group remained constantly at 83-83.5c, every shot raise it to 87-88c and after 1.5 minutes it returned to back to idle temp."

http://www.home-barista.com/levers/londinium-1-unstable-brew-temperature-t25444-10.html#p297202

This strongly suggests that the behaviour of the OP's machine is anomalous.


----------



## painty

AndyS said:


> Just for the record, Reiss and I had a lively exchange of emails (at least 18 by my count) leading up to me placing an order, receiving the machine, and reporting the leaky safety valve.
> 
> I first brought up the temperature variation issue in an email to him on 3/17. He didn't respond to that, which seemed out of character, so I sent it again on 3/19. After again receiving no response, I sent him a private message through this forum on 3/25. It also went unanswered.
> 
> So I get your point that Reiss may be unhappy to see this topic out in public, but if you were in my position, having bought a brand new machine and being more than 5000 km away from London, what would you have done?


Apologies, I jumped to conclusions there.


----------



## GlennV

AndyS said:


> Glenn, that is very interesting and at some point I will experiment with the sensor position. Out of curiosity, can you estimate how much faster is the heat transfer is from steam to copper rather than water to copper? Obviously, steam at 120C has greater heat content per gram but water is so much denser.


OK, I'm not a thermodynamicist, so take this with a grain of salt, but I would guess 2 to 4 times greater for steam/copper/water as compared to water/copper/water. The key is to look at the temperature drops for a fixed heat flow rate. In the water/copper/water case, if the fluids were still, then you would get two large temperature drops at the copper/water interfaces. In the former case you get just one (plus a much smaller drop at the steam/copper interface). So that's a factor of about 2. However, the water is not still; there's convection on the boiler side, and circulation in the thermosyphon. I've no idea how to estimate these flows, but I would have thought that the velocity in the thermosyphon would be greater, making the heat transfer more efficient on that side and the factor something greater than 2. This is all for small temperature differences though. More relevant here, perhaps, are the nonlinear effects. For example, efficient heat transfer at a steam/copper interface relies on the condensate being able to run off quickly enough and not form an insulating film. In practice this is all a bit of a dark art, which the guys at Fracino will have a far better handle on than any theoretician. So I shan't speculate on how the system is designed to work, but certainly if the heat exchanger were running in steam when it should be in water, or in water when it should be in steam, then you should expect to see a large change in behaviour.

Edit: Just to put this in context, my working assumption here is that the Londinium does what it says on the tin. Being such a simple design, there just aren't then that many things that could go wrong and account for the behaviour of Andy's machine.


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## JonR10

GlennV said:


> OK, I'm not a thermodynamicist, so take this with a grain of salt, but I would guess 2 to 4 times greater for steam/copper/water as compared to water/copper/water.


It's like an order of magnetude. The rate of heat transfer from steam will be far and away greater than the rate for liquid water. Here's a reference table showing overall (rough) heat transfer coefficients, and you may note that the heat transfer coefficient from steam/copper/water is much higher than the coefficient from water/copper/water http://www.engineeringtoolbox.com/overall-heat-transfer-coefficients-d_284.html

When you account for the additional mobility of the steam compared to the water, the rate of heat transfer picks up.


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## coffeechap

Andy you do like posting your trivia all over the place don't you? Strange that you didn't mention the excellent quality shots you had achieved on the Australian forum!


----------



## markant

Andy,

Reiss, do you think the thermosiphon is plugged or otherwise messed up? Perhaps the same junk that got in my safety valve also got in the thermosiphon pathway?

Don't know whether you already understood: Reiss is not talking about grit in the safety valve, he is talking about something in the solenoid! If so, the machine is probably overfilling the boiler! (So flushing the system, emptying the boiler with the hot water tap might get the shit out of the solenoid and overfilling problem over). If the boiler is overfilled, the safety valve might do strange things, I suppose..... (and/or the electronics might as well?)

Trying to think now what influence overfilling can have on the thermo siphon, since it is clear that it doesn't work in your machine as it should: time to get to the equilibrium between boiler temp (at certain pressure) and group temp is ridiculous after taking a shot. To be able to make back-to-back shots, this should not be much more than a few minutes.....

*Anyway, I think you cannot jump to conclusions about the brewing temperature differences between shots as long as the thermosiphon in your machine is not functioning properly. *

*
*

I guess the solenoid (or-->steering electronics?) is not working properly (safety valve hints to that) or that the thermosiphon is partly blocked.

Interesting (but also logic!) result from your measurements is the direct relationship between group temp and brewing temp.

I would like to see how to get L-1 quickly to equilibrium temp from zero with flushes. It seems from the graph of Eric (see above) that he flushed too early and too little to get there within Reiss's claim of 15 minutes. Also I would like to see how quickly the thermosiphon after a shot gets running again, meaning measuring the temperatures of both siphon pipes over time.

Wish I had the equipment to measure the temperatures.... Andy, could you help me out? I am from Warsaw, we have got a 'Conrad' shop in town. Please PM me with suggestions what to buy.

Mark


----------



## The Systemic Kid

Ran a temp test on my LI last night - here are the results.

Being curious, but not owning a Scace, I came across the following way of checking brew head water temp:

http://www.frcndigital.com/coffee/HowToTempCheck.html

*Method:* Used a Styrofoam cup with the bottom cut out and attached it to the brewhead to act as a chute under which I placed another Styrofoam cup cut down to hold exactly 50ml. Instead of using a milk foaming thermometer, used a Thermapen stick probe which reads much faster (less than three seconds) and is certified accurate to plus/minus 0.4c. The lever was pulled until the 50ml cup was exactly filled and the probe immediately inserted to record temperature. Over a four and a half hour period, I took 18 readings at random. Readings 3 & 4; 8 & 9; and 17 & 18 were back to back - two minutes between each reading. The range of temperature fluctuation throughout the 18 readings was 1.3c (92c to 93.3c).

View attachment 2324


The elegance of the above test is that it is very simple to replicate. All you need is a digital Thermapen probe which can be bought for £28.80 delivered. A word of caution is needed here. My test results don't prove all LIs are thermally stable (although I suspect they are) - but it does show that my LI is thermally stable to within 1.3c which I put down to the thermosyphon design coupled with the large mass brew head.


----------



## forzajuve

Nice work Systematic Kid. Good to have a set of data to get back to the OP so he can verify his concerns on his own machine against another. Always good to move away from the speculation and owner bias with some replicable results for comparison. I suspect this is what other users are finding and goes to show that the OPs L1 has some sort of error, although now this can be checked against this method.


----------



## sjenner

markant said:


> Andy,


Reiss, do you think the thermosiphon is plugged or otherwise messed up? Perhaps the same junk that got in my safety valve also got in the thermosiphon pathway?

Don't know whether you already understood: Reiss is not talking about grit in the safety valve, he is talking about something in the solenoid!

Mark

Actually that is not the case...

Many people use some sort of filtration to prepare their coffee water, it is the contention that sometimes microscopic pieces of charcoal, or some other material will enter the boiler, and given a particular piece of bad luck, somehow get lodged into the safety valve...

...The safety valve does not need to be held open to cause a problem, rather it is being stopped from shutting.

As far as I can tell Andy never had this problem, he may have a problem with part of the mechanism i.e. a faulty safety valve, but more likely, he turned down the boiler pressure for some other reason.

The mention of the solenoid is the possible reaction that it might have if it thinks that the boiler has not filled up yet... It keeps allowing cold water to pump through into the boiler and straight out through the safety valve... Which can be a tad messy, if you aren't watching.


----------



## NickR

A fascinating set of results Systematic Kid.. I used exactly the same method to test my Pavoni many years ago - the results were really terrible, however with a Pavoni the flow rate during the tests was utterly differant to the flow rate when actually making coffee. I've no idea how the lack of coffee would affect the L1 during these tests.


----------



## The Systemic Kid

AndyS's experience is perplexing which is why I decided to run my own test using an approach that is much more accessible, cost-wise. There are very people in a position to afford the cost of a Scace let alone have access to the equipment to prepare the portafilter basket for the probe which is a shame. What we need, if we want to speculate about this or that machine's performance, is a simple replicable test - the one I used can be set up for any machine and allow the user, if s/he is so minded, to conduct their own tests.


----------



## The Systemic Kid

NickR said:


> A fascinating set of results Systematic Kid.. I used exactly the same method to test my Pavoni many years ago - the results were really terrible, however with a Pavoni the flow rate during the tests was utterly differant to the flow rate when actually making coffee. I've no idea how the lack of coffee would affect the L1 during these tests.


Thanks Nick. I think it is very important when setting up a test to be careful about what it shows. Any test that attempts to measure what's going on inside the brewhead/portafilter basket is going to be open to challenge as you rightly point out because there isn't a puck of coffee present. All I set out to do was to extract 50ml of water and measure the temp to see if there were a wide range of resulting temps which there weren't. All I take from this is that the thermosyphon design on my LI - is working as it should and keeping the temp of extraction water within a very tight margin.


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## mathof

How do you do that "thank you" thing? I'd like to do it for this post.


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## The Systemic Kid

mathof said:


> How do you do that "thank you" thing? I'd like to do it for this post.


Hi mathof under each post, there's a 'thanks' box - towards the left - next to 'promote to article'. If you want to 'thank' a post - just click on it.


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## markant

sjenner said:


> Reiss, do you think the thermosiphon is plugged or otherwise messed up? Perhaps the same junk that got in my safety valve also got in the thermosiphon pathway?


Don't know whether you already understood: Reiss is not talking about grit in the safety valve, he is talking about something in the solenoid!

Mark



> Actually that is not the case...


Actually that IS the case: msg #23 of the thread, written by Reiss



> 'You are correct
> 
> It is the safety valve
> 
> If there is a piece of grit in the solenoid it can cause this
> 
> [unquote]
> 
> and msg #24 written by AndyS:
> 
> 
> 
> 
> Per your instructions, I did perform this maneuver several times, although it puzzled me how flushing the fill solenoid could clear a piece of grit from the safety valve.
> 
> [unquote]
> 
> Clearly some misunderstanding here.... where ever this grit may be or may not be.
> 
> Mark
Click to expand...


----------



## sjenner

markant said:


> Don't know whether you already understood: Reiss is not talking about grit in the safety valve, he is talking about something in the solenoid!
> 
> Mark


Actually that IS the case: msg #23 of the thread, written by Reiss



> 'You are correct
> 
> It is the safety valve
> 
> If there is a piece of grit in the solenoid it can cause this
> 
> [unquote]
> 
> and msg #24 written by AndyS:
> 
> 
> 
> 
> Per your instructions, I did perform this maneuver several times, although it puzzled me how flushing the fill solenoid could clear a piece of grit from the safety valve.
> 
> [unquote]
> 
> Clearly some misunderstanding here.... where ever this grit may be or may not be.
> 
> Mark
> 
> 
> 
> Deleted text
Click to expand...


----------



## redpig

BTW, earlier on in this megathread, there was a request for other L1 owners to strap a thermocouple to their group. I don't mind doing this, but are there any recommendations for cheap thermocouples that will do the job? My main reason for not doing it is because I don't own one and my L1 has unbelievably improved the consistency of my espresso pulls to the point where I wasn't ever motivated enough to do more rigorous evaluation


----------



## rodabod

Someone buy The Systemic Kid a pint!


----------



## coffeechap

Wow all these new forum members and loads from the states coming to the rescue of the OP, not at all strange!


----------



## AndyS

markant said:


> Don't know whether you already understood: Reiss is not talking about grit in the safety valve, he is talking about something in the solenoid! If so, the machine is probably overfilling the boiler! (So flushing the system, emptying the boiler with the hot water tap might get the shit out of the solenoid and overfilling problem over). If the boiler is overfilled, the safety valve might do strange things, I suppose..... (and/or the electronics might as well?)


Yes, I understood that Reiss is talking about grit in the SOLENOID. But my machine is not yet plumbed in, it is running off the tank. So a solenoid that didn't close all the way would not overfill the boiler since the boiler pressure is higher than the atmospheric pressure. In other words, I don't think the solenoid is malfunctioning.



markant said:


> *Anyway, I think you cannot jump to conclusions about the brewing temperature differences between shots as long as the thermosiphon in your machine is not functioning properly. *


Yes, it appears that I have a problem with the thermosiphon, but I haven't solved it yet. Improper water level in boiler? Blocked thermosiphon? Don't know yet.



markant said:


> I would like to see how to get L-1 quickly to equilibrium temp from zero with flushes. It seems from the graph of Eric (see above) that he flushed too early and too little to get there within Reiss's claim of 15 minutes. Also I would like to see how quickly the thermosiphon after a shot gets running again, meaning measuring the temperatures of both siphon pipes over time.


Remember that Eric and I are in the US, so our machines have the lower wattage 115v heating elements.



markant said:


> Wish I had the equipment to measure the temperatures.... Andy, could you help me out? I am from Warsaw, we have got a 'Conrad' shop in town. Please PM me with suggestions what to buy.


I don't know what a Conrad shop is, but you want to find a thermocouple indicator with a "bead type" probe. The indicator is the part you read temperatures on, usually with a digital display. The bead probe is a long wire that plugs into the indicator on one end, and measures temperature at the very tip of the other end. Some of the units coming over from China nowadays are unbelievably cheap -- like $20-40US for the whole thing. PM me if you have more questions.


----------



## AndyS

redpig said:


> BTW, earlier on in this megathread, there was a request for other L1 owners to strap a thermocouple to their group. I don't mind doing this, but are there any recommendations for cheap thermocouples that will do the job?


Redpig, please see my reply to markant. Also, here is an example of an extremely cheap setup that is selling via Amazon in the States. I suppose something like that is available wherever you are located.


----------



## AndyS

The Systemic Kid said:


> Ran a temp test on my LI last night - here are the results.
> 
> Being curious, but not owning a Scace, I came across the following way of checking brew head water temp:
> 
> http://www.frcndigital.com/coffee/HowToTempCheck.html....
> 
> ....The elegance of the above test is that it is very simple to replicate. All you need is a digital Thermapen probe which can be bought for £28.80 delivered. A word of caution is needed here. My test results don't prove all LIs are thermally stable (although I suspect they are) - but it does show that my LI is thermally stable to within 1.3c which I put down to the thermosyphon design coupled with the large mass brew head.


Hi Systemic:

Thank you for taking the time to do that. Of course this type of test is not nearly as accurate as one using a Scace device, but still, it appears that your machine is a lot more stable than mine.


----------



## mb0

In case you might be interested, there is a blog post about the group temperature and temperature profile during extraction of a bosco:

http://comingsooncoffee.wordpress.com/2012/04/17/bosco-spring-lever-scace2-test/

What is interesting is, that the initial group temperature also shows a great drift, but stabilizes the more shots one pulls (at least the

bosco is made for espresso mass-production...) in a row. The temperature profile during extraction seems to be a continuous drop of 3°

regardless of intial group temp.

actually, these are the only numb3rs i could find about the bosco/idro group. anyone else got numb3rs?


----------



## erics

Greetings - I am experiencing the same temperature frustration as AndyS and have not yet managed to solve the problem. I primarily drink cappy's and my taste buds are, perhaps, not as refined as most. I do, however, have experience in conducting temperature tests and this machine (Londinium 1) does not pass muster. The specific problem is that, at a given pstat setting (1.30 bar max in my case as I type), group temperatures can vary all over the map. This results in equally varying temperatures of water presented to the coffee. Whether this can be discerned depends on the operator but I will do my best (soon) to post some shot temperature graphs at equal pstat settings.


----------



## coffeechap

wow yet another amerian jumping on the forum to the defence of Andy and the detriment of the L1, might be interesting to do a sweep stake as to how many more will come out of the woodwork?


----------



## JonR10

coffeechap said:


> wow yet another amerian jumping on the forum to the defence of Andy and the detriment of the L1, might be interesting to do a sweep stake as to how many more will come out of the woodwork?


Wow. Thanks for the warm welcome.

I found this forum and specifically this discussion when someone called attention to this thread on a US forum.

http://www.home-barista.com/levers/londinium-1-unstable-brew-temperature-t25444.html

I for one have been keenly interested by this machine, so I came to see what people are saying about it and learn about others' experiences. Of course I also know AndyS so I'm particularly interested in his take on the machine.

If folks from other locations aren't welcomed here then perhaps that should be posted somewhere in the forum rules or guidelines, or perhaps it could be mentioned in the "new members" section.

Cheers,

J


----------



## AndyS

coffeechap said:


> wow yet another amerian jumping on the forum to the defence of Andy and the detriment of the L1, might be interesting to do a sweep stake as to how many more will come out of the woodwork?


Hi coffeechap:

For me this thread is about trying to coax consistently excellent espresso from the Londinium 1. It has absolutely nothing to do with "UK versus USA," or "AndyS trying to hurt Reiss Gunson's business," or any of the other off-topic comments that you keep posting.

Now it is possible (but I think unlikely) that the 115v Londinium 1 differs from the standard 230v model in more than simply its electrical spec. Perhaps port sizes, pipe sizes, or other tuning parameters have been changed. That might explain the issues that erics and I are having. Again, it seems possible but not likely.


----------



## coffeechap

If that is the case Andy then why post on an Australian forum about the bias on this forum towards the L1 I definitely think that you have an issue with your machine per se but don't think this is necessarily the medium for you to air your dirty laundry. I have followed the thread in Australia on a forum that is biased towards its sponsors and felt that the underhand methodology employed by the moderator to get his freind to write a supposedly unbiased evaluation was strictly not cricket. You cemented those comments with your belittling remarks of this thread.

I don't have an issue with anyone coming onto this forum and expressing their help and interest to forum members as indeed some of the new members have. Most people want to help each other and learn about making great coffee I hope that that is the motive of the others joining recently.

JonR my apologies I have only heard positive things about you and did not mean to generalise as undoubtedly i did in my comment.


----------



## RoloD

Intereresting post on Reiss' blog today:

"We stand by our claim that LONDINIUM I is thermally stable. By this we mean the group sits at the correct idle temp for hours on end, allowing you to walk up and pull an exceptional shot with no flushing. By thermally stable we also mean that you can pull consecutive shots until your arm falls off and the group won't over heat - indeed we have a customer in Nova Scotia who pulled shots on his LONDINIUM I consecutively for an hour and could not get it to over heat

But as usual there was the sniping from the sidelines that we were making unsubstantiated claims and that riles me because I know of no espresso machine manufacturer that releases their test data and I see no reason why we should be the first. Secondly, unlike everyone else we are the only espresso machine manufacturer that I am aware of that allows you 30 days from the day your LONDINIUM I arrives to contact us and say for whatever reason that it hasn't met your expectations and could we please arrange for it to be taken away

So here's my compromise; on Monday 15 April I will sign a contract with a company of specialist thermal instrumentation engineers in Oxford to make 100 temperature probes that will fit into a modified portafilter. It will be designed to have coffee loaded into the portafilter basket and it will plug directly into you laptop via a USB connection, eliminating the need for a data logger. Then if you are more interested in the numbers than the coffee you will be able to fit this device into a Idrocompresso, a Bosco, a Quickmill Achille, or indeed any machine that uses this group and benchmark the LONDINIUM I against it. With a bit of luck that will keep the coffee by numbers guys happy, and let the rest of us just get on with enjoying the espresso and getting some work done

LONDINIUM I is thermally stable - how else do you explain so many happy customers?

The most complex taste sensor in the world is fitted as standard equipment inside your mouth; its called your tongue"


----------



## lookseehear

RoloD said:


> Intereresting post on Reiss' blog today:
> 
> "We stand by our claim that LONDINIUM I is thermally stable. By this we mean the group sits at the correct idle temp for hours on end, allowing you to walk up and pull an exceptional shot with no flushing. By thermally stable we also mean that you can pull consecutive shots until your arm falls off and the group won't over heat - indeed we have a customer in Nova Scotia who pulled shots on his LONDINIUM I consecutively for an hour and could not get it to over heat
> 
> But as usual there was the sniping from the sidelines that we were making unsubstantiated claims and that riles me because I know of no espresso machine manufacturer that releases their test data and I see no reason why we should be the first. Secondly, unlike everyone else we are the only espresso machine manufacturer that I am aware of that allows you 30 days from the day your LONDINIUM I arrives to contact us and say for whatever reason that it hasn't met your expectations and could we please arrange for it to be taken away
> 
> So here's my compromise; on Monday 15 April I will sign a contract with a company of specialist thermal instrumentation engineers in Oxford to make 100 temperature probes that will fit into a modified portafilter. It will be designed to have coffee loaded into the portafilter basket and it will plug directly into you laptop via a USB connection, eliminating the need for a data logger. Then if you are more interested in the numbers than the coffee you will be able to fit this device into a Idrocompresso, a Bosco, a Quickmill Achille, or indeed any machine that uses this group and benchmark the LONDINIUM I against it. With a bit of luck that will keep the coffee by numbers guys happy, and let the rest of us just get on with enjoying the espresso and getting some work done
> 
> LONDINIUM I is thermally stable - how else do you explain so many happy customers?
> 
> The most complex taste sensor in the world is fitted as standard equipment inside your mouth; its called your tongue"


Other manufacturers don't release test information about their machines but they also don't (to my knowledge) make the same claims that Reiss has done.

My opinion on this is very simple - if you are selling something and you make claims about its performance then you *have* to be able to back it up or you lose credibility. This applies to cars, clothing etc as much as it does about espresso machines.

Other test have shown that it probably is temperature stable which is great news as it should put this to rest, although perhaps there is a slight question mark over the 115v machines or perhaps lower pressurestat settings. I don't know but I think my point stands that if tests had been done at the prototyping stage at different pressurestat settings and under different voltages then Reiss could have issued recommended settings to keep the temp stability performing as it should.

I have no vendetta against Reiss or Londinium but I feel very strongly that there has to be a fair marketplace. What happens if Gaggia make a statement that the classic is extremely thermally stable? We all know that isn't the case but it muddies the waters when you aren't sure what information is correct and what isn't.

Also - from the above does Reiss mean he's going to do testing himself or is he offering these testing kits to sell? In my opinion he should be doing the tests himself.

Again just to clarify - this isn't about the quality of the coffee it's about the credibility of the manufacturer.


----------



## The Systemic Kid

lookseehear said:


> Again just to clarify - this isn't about the quality of the coffee it's about the credibility of the manufacturer.


Er, I think you will find it's both. Reiss has stuck his reputation and credibility behind LI and the coffee quality it produces -think he deserves credit for this.



lookseehear said:


> My opinion on this is very simple - if you are selling something and you make claims about its performance then you *have* to be able to back it up or you lose credibility. This applies to cars, clothing etc as much as it does about espresso machines.


Fair point, but so far, there are only a couple of people challenging LI's thermal stability on this forum - one of whom has, to date, published some data which prompted me to do my own testing out of curiosity which found that the thermal stability was within a range of 1.3c. Usually, a piece of equipment's performance criteria are verified or not under lab conditions to ensure that findings are accurate, consistent and unbiased. But there can be a world of difference between lab findings and field experience. Look at car manufacturers' claims for fuel consumption and consumer experience.

I am intrigued by Reiss's suggestion to make 100 probes. I would be more than happy to do a field trial with it. As it happens, I've just ordered a Two Channel 2 K-Type Digital Thermometer Thermocouple Sensor as recommended by AndyS to conduct a few more checks of my own and broaden the pool of data on LI's thermal stability.


----------



## RoloD

lookseehear said:


> My opinion on this is very simple - if you are selling something and you make claims about its performance then you *have* to be able to back it up or you lose credibility. This applies to cars, clothing etc as much as it does about espresso machines.


That is reasonable. The thing is, all the initial user reports supported the claim the LI is thermally stable - it's what almost all users remarked upon; certainly you can leave it on all day with no noticable change in the coffee it produces. To that extent, the claims were substantially verified by satisfied users.

It is only when Scace readings were made that these claims began to be challenged from which one can deduce either:

i)the Scace readings were wrong

ii)the machine used for the readings was malfunctioning or

iii)the Scace readings were correct but not significant for this type of machine (it has been suggested that the built-in temperature profiling of a commercial lever group makes initial group temperature much less important)

I once had a Gaggia Classic with an Auber PID control. I could adjust the temperature within a degree and get a read out of the boiler temperature. As far as the numbers went, this machine was 'phenomenally stable'. Let me assure you it wasn't and the adjustment up and down a degree had little relation to actual brew temperature. There really is no comparison between the coffee I got out of the Gaggia and the machines that followed - an Olympia Cremina and then the Londinium I; it's like comparing a Nespresso machine to an E61 (although the PID was a good improvement and the Classic is still great value for money).

So I absolutely agree the manufacturer should back up his claims. Reiss has done this by offering money-back guarantee, carriage paid, if you aren't happy with the machine. That, to me, is more important than the numbers as, from my own experience, numbers often don't add up to much.


----------



## 4085

I think that a line needs drawn under this soon. Perhaps once these sensors are available nd have been used and the data crunched, it will prove what we think we know now ie on the whole, the L1 is stable however, there are in circulation one or two machines that are not. The only way for these rogue machines to be really sounded out would be to be returned to the manufacturer and allow him the time and space to conduct his own set of measurements and then compare them against the original data.

In any manufacturing system, no matter how good the quality control, there will always exist the odd system error. What is clear, to me anyway, is that Andy probably has such an anomaly but that is simply not going to drag the rest of the machines down with it.

Andy, declare your intentions! Are you going to keep your machine and hope it can get a fix, or send it back for a refund, and if you do that, are you going to try your hand with another?


----------



## lookseehear

The Systemic Kid said:


> Er, I think you will find it's both. Reiss has stuck his reputation and credibility behind LI and the coffee quality it produces -think he deserves credit for this.


You clearly missed my point.

I wasn't saying the quality of the coffee wasn't important - it clearly is. What I was saying is that (for me) if a manufacturer claims something that can't be backed up and hasn't actually been verified then they lose credibility. That credibility can't be regained by saying that the coffee's good, even if everyone that bought one is saying that the coffee is good.

It is also not OK to make claims which may or may not be true then qualify them with guarantees of refunds if you aren't happy - there is always hassle associated with returning a large, high value item like this, especially if it has been sent internationally.



The Systemic Kid said:


> Fair point, but so far, there are only a couple of people challenging LI's thermal stability on this forum - one of whom has, to date, published some data which prompted me to do my own testing out of curiosity which found that the thermal stability was within a range of 1.3c. Usually, a piece of equipment's performance criteria are verified or not under lab conditions to ensure that findings are accurate, consistent and unbiased. But there can be a world of difference between lab findings and field experience. Look at car manufacturers' claims for fuel consumption and consumer experience.


I agree it looks like the standard L1 is stable - the lower voltage L1 and at lower pressurestat settings might yet not be though. If Reiss had tested this he would know the 'safe' pressurestat range to use to ensure the group works as intended.


----------



## RoloD

lookseehear said:


> I wasn't saying the quality of the coffee wasn't important - it clearly is. What I was saying is that (for me) if a manufacturer claims something that can't be backed up and hasn't actually been verified then they lose credibility. That credibility can't be regained by saying that the coffee's good, even if everyone that bought one is saying that the coffee is good.


The stability of the LI is verified by the fact you can leave it on all day,it doesn't need cooling or warming flushes (apart from the intial one), you can extract espresso after espresso and the coffee is still good. The group temperature is fluctuating as you use it by its nature. A particular set of measurements doesn't invalidate these claims, particularly when there is no comparison to other similar lever machines. Spring lever machines, by their nature, fluctuate in temperature but still produce consistently good coffee.



> It is also not OK to make claims which may or may not be true then qualify them with guarantees of refunds if you aren't happy


It is not that Reiss claims are 'not true', it's really an interpretation of what the terms 'temperature stability' means. I would claim, despite measurements, for its class and in practice, the LI has great temperature stability.


----------



## Glenn

JonR10 said:


> If folks from other locations aren't welcomed here then perhaps that should be posted somewhere in the forum rules or guidelines, or perhaps it could be mentioned in the "new members" section.


Folks from all around the world are very welcome.

There are no restrictions on which country a member must come from to be a member.


----------



## lookseehear

RoloD said:


> The stability of the LI is verified by the fact you can leave it on all day,it doesn't need cooling or warming flushes (apart from the intial one), you can extract espresso after espresso and the coffee is still good.


Oh ok so when Reiss said it was extremely stable he meant about as stable as a Gaggia classic? I could leave that on all day and walk up to it and pull a decent shot.



RoloD said:


> The group temperature is fluctuating as you use it by its nature. A particular set of measurements doesn't invalidate these claims, particularly when there is no comparison to other similar lever machines. Spring lever machines, by their nature, fluctuate in temperature but still produce consistently good coffee.


I don't care what happens while you're pulling a shot. In the video Reiss made it very clear that the temp drops off as the shot progresses so there's nothing misleading about that.



RoloD said:


> It is not that Reiss claims are 'not true', it's really an interpretation of what the terms 'temperature stability' means. I would claim, despite measurements, for its class and in practice, the LI has great temperature stability.


Well as long as we can just apply our own definition to 'temperature stability' then everything's rosy.

I'm pretty sure you said you were bowing out of this thread a good few pages ago anyway?


----------



## The Systemic Kid

lookseehear said:


> Well as long as we can just apply our own definition to 'temperature stability' then everything's rosy.





> ...."on Monday 15 April I will sign a contract with a company of specialist thermal instrumentation engineers in Oxford to make 100 temperature probes that will fit into a modified portafilter. It will be designed to have coffee loaded into the portafilter basket and it will plug directly into you laptop via a USB connection, eliminating the need for a data logger."


Well I guess the few who have reservations concerning Reiss's claims regarding LI's thermal stability, will welcome his intriguing blog post.


----------



## lookseehear

The Systemic Kid said:


> Well I guess the few who have reservations concerning Reiss's claims regarding LI's thermal stability, will welcome his intriguing blog post.


If you'd read my posts - I agree that the L1 is probably fine temperature stability wise but I'm just a bit baffled this wasn't done before hand.


----------



## RoloD

lookseehear said:


> I'm pretty sure you said you were bowing out of this thread a good few pages ago anyway?


Apologies. I did and I shall. Goodbye.


----------



## EricC

It would appear that a member on Home-Barista may have found what has caused the inconsistency in temperatures.

Please see the link below.

http://www.home-barista.com/levers/londinium-1-unstable-brew-temperature-t25444-140.html

Regards

Eric


----------



## AndyS

Here are a few more observations from ongoing use of the Londinium L1. There are more questions than answers here, but hopefully this is a (collaborative) work in progress.

It has become evident to multiple users that proper "care and maintenance" of the L1 thermosiphon ("TS") is a bit more challenging than we first thought. In particular, if the TS "stalls" (ie, stops circulating) for an extended period of time, group temperature will rapidly drop. A small stall with a small temperature drop is desirable for a short period right after each shot, to bring the group back down to "normal" temperature. But for each 10 degrees that the group continues to cool past normal, the brew water temperature will be about 7 degrees cooler.

How cool is too cool? What's the optimum temperature range? Is the optimum range wider in lever machines compared to pump machines, since most levers provide a declining temperature profile anyway? These are questions that need much more study, however my general taste observations were posted here.

Based on reports of pump machines, where temperature stability has long been a focus, I would suggest for pump machines that +/- 1F (0.5C) might be considered "excellent" and +/- 0.5F (0.3C) might be considered "phenomenal."

For lever machines, what should we consider to be the corresponding ranges? Twice times as wide? Four times? Six times?

Optimum ranges aside, with help from others I have learned something about maintaining a proper Londinium thermsiphon. At Reiss's recommendation, I thoroughly lubed the group and also made sure to move the lever without hesitation when pulling real shots and/or Scace "shots." Also, the technique for using a Scace Device with the L1 probably needs to be different from that which is appropriate for pump machines.

With the L1, I had been letting six seconds worth of water (~3 grams) pass through the Scace with the lever in the full down (preinfusion) position. Then I would proceed with the test shot using spring pressure. This procedure is similar to how I pull a normal shot on the L1 with real coffee. But this technique seems to disrupt the thermosiphon. EricS pointed me to a post by JohnB on Home-Barista, where John manually blocked the Scace orifice during the preinfusion period when testing a lever machine. When I tried these things, my L1 group temperatures were more stable.

Still, the temperatures are far from what I would call "phenomenally" stable. In the morning, if I follow Reiss's instructions for warming the group, I run 450ml through the group and wait 8 minutes. But this leaves the group way too cool at around 155F (67C). A second flush raises the group to the low 170's (~78C), still fairly cool. Then, over the course of several hours, the group temperature continues to rise, leveling out around 192F (89C), which is too hot for my taste. This range of about 20F (11C) needs improvement, IMHO. For this reason, I asked Reiss to send a TS restrictor, and I hope that will give better control of group temp.

Without the thermometer on the group, I would have no idea this was going on, and I could easily ascribe a mediocre shot to "operator error."

Another interesting phenomenon is that the L1 TS has three distinct states. I'd call them, "stalled," "normal," and "reverse." Stalled (little or no flow) is what occurs briefly after every shot, and also, as discussed above, when things have gotten disrupted. Normal is what Reiss drew up in the L1 schematic diagram.  Hot water from the boiler flows into the top group connection and cooler water returns to the boiler through the bottom group connection. Reverse is what I have often observed after attaching thermocouples to the upper and lower TS tubes. The TS can run for extended periods of time with *hotter water entering the bottom of the group and cooler water leaving the top of the group.* Obviously this is not how the TS was designed to run, and eventually it flips back to Normal operation when disturbed by a shot pull. I haven't yet figured out what effect it has on the thermal performance of the machine, but this is peculiar. I imagine it has to do with the HX being mounted horizontally, with the two ends being of equal temperature. See attached jpgs for details (the green line on top indicates normal flow, the yellow line on top reverse flow).


----------



## rodabod

Andy, have you ever thought of going into espresso machine design and construction?


----------



## The Systemic Kid

rodabod said:


> Andy, have you ever thought of going into espresso machine design and construction?


Now, that's a good idea.


----------



## Bob_McBob

In addition to blocking the port during pre-infusion, I generally restrict the lever motion to give an appropriate flow rate when I am doing Scace testing. I'm not sure if the lower spring pressure on the L1 makes this less of an issue; the Strega will power through the entire contents of the piston chamber in something like 10-15 seconds, which doesn't simulate my normal use very well.


----------



## AndyS

rodabod said:


> Andy, have you ever thought of going into espresso machine design and construction?


It's not that difficult for an individual to modify a commercial espresso machine in order to "improve" some aspect of its performance. As an independent experimenting with your own machine, you don't have to worry about appearance, warranties, safety considerations, durability, profit margins, regulatory approvals, etc.

If you're a commercial manufacturer, on the other hand, all those worries become crucially important. What Reiss has done in introducing the L1 is a huge task and a complex one; he certainly has my respect for pulling it off.


----------



## AndyS

Bob_McBob said:


> the Strega will power through the entire contents of the piston chamber in something like 10-15 seconds, which doesn't simulate my normal use very well.


Yes, the WCE standards call for 75ml of water to be discharged in 25 secs. That is probably twice the flow rate many of us prefer in our daily shot making.


----------



## AndyS

With a repeated group flushing and repeated purging through the top plug on the group neck, my L1 is now running at reasonably stable temperatures. It is too early to know if this will continue, but I am hopeful. Below is a graph from this evening showing warmup and one espresso shot produced. Thermosyphon flow is reverse for most of this plot (hotter water flows into the lower group connection, colder water flows out of the upper group connection)






.


----------



## 4085

But the Strega lets you control both the amount of water going into the group and the extraction rate at which it comes out


----------



## LeverAspirations

And your point is?


----------



## 4085

AndyS said:


> Yes, the WCE standards call for 75ml of water to be discharged in 25 secs. That is probably twice the flow rate many of us prefer in our daily shot making.


The point is, only if you let it


----------



## LeverAspirations

Apologies. Reading on a phone. It seemed a bit of a non sequitur from the post immediately preceding. Also, drunk, sleep deprived and belligerent.


----------



## 4085

We have a lot in common then this morning!


----------



## LeverAspirations

The other week I was in the middle of a particularly stressful week and a client caught me (thanks video Skype!), sipping a particularly nice riesling at 10am. Since I usually present a demeanor of complete control, she was unnerved to day the least.

Not a habit. Fun to do every now and then, however.


----------



## AndyS

Two weeks ago I reported that with repeated flushing and purging my L1 was running with reasonable temperature repeatability. Further use may or may not confirm that, depending on what "reasonable" means to you.

The graph attached below is typical and shows my espresso-making activity this morning, starting at about 8 am. The L1 had been turned on two hours earlier via an automatic appliance timer.

From about 8:19 am to 8:58 am I pulled three shots. The group temperature sagged about 6F (3.3C) from first shot to last. That would correspond to an average brew temperature that sagged about 4F (2.2C) from first to last, which I would call "reasonable."

Unfortunately the group temperature continued to sag, reaching a low point as the thermosiphon stalled around 9:19am. If I had pulled a shot at that point (which I didn't), the average brew temperature would have declined about 13F (7.2C) compared to the first shot (a one degree change in group temp produces about a 0.7 degree change in average brew water temperature). I would not call that acceptable performance.

After the stall you can see the group temperature slowly rising. After a couple hours it gets nearly gets back to where it started.

You can also see the signature L1 thermosiphon flip flop, where the flow reverses after the first shot and then reverses again after the third shot. This is peculiar, but doesn't seem to have a significant effect on overall performance.

I'm aware that some people (notably fransg and kfir) report that once they have flushed and purged the thermosiphon, they get more stable results that appear to continue indefinitely. I am not so lucky; neither is erics.

Reiss has stated that a non-return valve in the "trombone" piping from the boiler to the heat exchanger will solve the thermosiphon stall issue. I have not received these parts yet, so I can't comment on the effectiveness of this addition.

I should mention that my thermosiphon has a restrictor in the piping. This was originally supplied by Reiss with about a 2.5mm orifice. I reamed it out, gradually going up to a 3/16" (~4.75mm) orifice. The purpose of the restrictor was to prevent idling group temperatures from getting too high. They were ending up in the 193-194F (90F) range, and the resulting brew temperatures seemed a little too hot for my tastes. The 2.5mm orifice cooled things down too much, so I gradually stepped up to the present dimension. The orifice probably slows thermosiphon temperature recovery somewhat, but the stalls happen with or without the orifice.


----------



## AndyS

As mentioned previously, Reiss sent me the non-return valve and associated fittings to replace the original heat-exchanger feed piping. I've been using the new setup for the past few days, and I'm happy to report that the machine's temperature performance is much more stable now. Following Reiss's advice, after the installation I spent a bit of time purging air from the port atop the group neck port and also repeatedly with full open port flushes. And I'd still recommend a moderate flush (50-75 ml) each morning, followed by a ~5 minute wait for the group to return to idling temperature. But then the L1 seems to run in a nice predictable manner (the graph below is typical of current data logs).

Is this the end of the story? I think not; I have never been able to leave "well enough alone" in any espresso machine, and there are modifications to the L1 that I would like to test and report on later. But for now, the L1 with non-return valve is easy and fun to use, looks great, and makes very tasty espresso.


----------



## The Systemic Kid

Good to hear your trials and tribulations with temp fluctuation are over.


----------



## painty

That's good news. Looking forward to hearing how the mods go...


----------



## 4085

I remember suggesting that the L1 was work in progress and being told by some that I was wrong. At the time, the word 'evolution' crossed my mind, as after all, anything that evolves usually becomes better through that process.


----------



## RoloD

dfk41 said:


> I remember suggesting that the L1 was work in progress and being told by some that I was wrong. At the time, the word 'evolution' crossed my mind, as after all, anything that evolves usually becomes better through that process.


Well, I criticised your 'work in progress' comment because I have the first production model and it works great - 'work in progress' sounds like it is unfinished when already it does a first rate job. However, any small run specialist product will and should constantly evolve and be refined as user feedback comes in. I guess it's a matter of emphasis - 'constantly evolving' sounds positive, 'work in progress' sounds negative.


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## 4085

Rolo, beauty is in the eye of the beholder. If you want to sit there and think that in reality, there is any difference between 'work in progress' and 'evolutiuon', then away you go mate! Are you really suggesting to me, that no matter how good or bad a product might be, the consumer and owners have no right to offer an opinion that may differ from yours, without receiving a lecture in a school teacher type way, from you!

On a lighter note, I do not expect you take any more offence about anything I say to you, than I take offence at anything you may say to me.....and that is none! The thing about opinions, is that we all have one and we can all be right in our own way.

Here endeth todays lesson!


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## The Systemic Kid

Since my L1 took up residence in my kitchen and we began to get to know each other, several things have struck me. Yes, it's a stonking machine capable of producing stellar shots and it looks stunning. But there was something I couldn't quite put my finger on until Craig and Paul - the guys behind the HG One - did. It's the feel of the thing - it's so damn tactile - you engage with it in the same way you engage with the HG One. Craig and Paul's review says it all.

http://hg-one.com/londinium-i/


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## 4085

Patrick, I think you and are both new to lever machines, and therefore are experiencing shot quality, that we have not before encountered. This is therefore difficult for others in a similar position to identify with, as they probably think we are spouting garbage! One of the first things I have noticed, is that since switching from pump machines my palate is demanding a darker level of roasting. I have no idea as to why that might be, but lighter beans I used to enjoy now do nothing for me.

The L1 is a pleasure to own, with or without its foibles/mannerisms/faults/features, call it what you will. The only thing that slightly irks me, is the lack of attention to detail such as the drip tray, the horrible handles and the fact that it is definitely the twin ugly sister of the Cherub! If you look back at many machines, especially Italian ones, there are a lot of memorable shapes and sizes. To me, this is a classic case of someone inventing a brilliant machine, but forgetting to make it a little sexy.


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## RoloD

dfk41 said:


> Rolo, beauty is in the eye of the beholder. If you want to sit there and think that in reality, there is any difference between 'work in progress' and 'evolutiuon', then away you go mate! Are you really suggesting to me, that no matter how good or bad a product might be, the consumer and owners have no right to offer an opinion that may differ from yours, without receiving a lecture in a school teacher type way, from you!


 Absolutely not suggesting that, of course everybody has a right to offer opinion and I take no offence if people disagree with mine. The various discussions over the LI have, in the end, turned out to be very fruitful. I've already made the point about the phrase 'work in progress', so I won't make it again. Sometimes I have to suffer for having done a degree in philosophy.


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## coffeechap

But I think us unfortunate uneducated folk:act-up: take work in progress to mean exactly that, a product that is still evolving, the L1 will keep getting better and better, improving on what is a fab machine, with its own small issues. Reiss is certainly a person who is constantly trying to improve his baby. Sometimes we just drill down into terminology too much on here, as one man, or woman's chocolate is another's cocoa.


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## The Systemic Kid

Anything made by human hand can be improved but it isn't as simple as it seems. The Mark I Golf GTI which is acknowledged as THE hot hatch wasn't at all improved in subsequent evolutions which were change for change sake. Same with the Peugeot 205. I hope Reiss doesn't fall into the same trap.


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## coffeechap

I don't know I thought my 16v mk2 big bumper edition golf was the epitome of hot hatch and to many vw enthusiasts was the best golf ever made and what about the vr6! And what about the mk2 with the vr6 shoehorned in


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## painty

Which mk2 with VR6? : )


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## coffeechap

Ah but that is the point of customising, imagine my despair when my mate parked his pride and joy mk2 next to mine and said check this out, lifted the bonnet and showed me the vr6 engine in all its glory!


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## painty

Yes mk2 with VR6 is a lovely combo


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## The Systemic Kid

With 'evolution' the Golf, got bigger in size as did the Polo with the latter, eventually, being ad big as the Mark I Golf. Subsequent Golfs got bigger and heavier and heavier in part due to EU safety legislation and lost the razor sharp drive feel the Mark I was famed for. I think the original Mark I GTI had a 1600cc engine and was pretty damn quick at the time.


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## coffeechap

But not as good or quick as the mk2 16v 1800 which although the purists say the mk1 was the original, vw proved you could make it better, agreed all the subsequent golfs went down hill after that, which brings us back to the L1. Andy s has by default created the first of the improvements to the L1, I.e the non return valve, I am sure that subsequent tweaks will improve it further, but I don't think that the basics of that machine will ever change, nor should it.


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## shrink

The mk2 1800 gti is the jewel In the vw history. It was a definite improvement over the mk1 and was the last great gti they made. The mk5 gti was a decent car in modern times, but still fat and bloated by mk2 standards. The newest one is just dreary in every possible way.


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## coffeechap

Yeh man I loved mine tricked it out with an outstanding custom audio install, only moved on to an Audi tt convertible after many years of fun


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## AndyS

coffeechap said:


> what about the mk2 with the vr6 shoehorned in


This thread has taken an interesting digression! Below is photo of me at the Audi dealer the day I traded in my Corrado VR6. Perhaps you can tell from my expression that it was a sad day for me, indeed -- although the Audi was a far more reliable vehicle.


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## coffeechap

Noooooo I hope the Audi was something special.....


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## painty

You have impeccable taste! Always wanted one but out of my league.


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## The Systemic Kid

coffeechap said:


> Noooooo I hope the Audi was something special.....


Yeah, like the legendary Audi Quattro. Well, it was good enough for Gene Hunt.


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## 4085

I was an RS2000 man. Had several over the years. Maybe not as fast as a Golf or Peugeot, but British!


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## AndyS

coffeechap said:


> Noooooo I hope the Audi was something special.....


Nothing special, just an average A4. But at least it was a stick shift,: a "lever machine," if you will....


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## coffeechap

That surprises me andy that the tweeker you are sold out for an a4, go and chastise yourself man


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## coffeechap

Porsche cayman is my next car


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## AndyS

coffeechap said:


> That surprises me andy that the tweeker you are sold out for an a4, go and chastise yourself man


Unfortunately my Corrado must have been built on a Monday; I loved the car, but its succession of mechanical difficulties seemed never-ending. After the 3 yr warranty ran out, I had to pay for all the repairs personally, so the expense and uncertainty eventually made the trade-in an acceptable option. The A4 felt like driving a lorry compared to the Corrado, but at the time I just had to make a change....


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## coffeechap

Good job your taste in espresso machines is impeccable


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## CoffeeDoc

What about a Tuscan!

Paul


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## dsc

I'll dig out this old dinosaur of a thread to discuss a few issues I've been having recently. I've made a very simple temp measurement basket with a TC epoxied to an old ridged basket and the results are rather interesting (for me anyway).









The first three peaks are flushes at different boiler pressure, I've had the boiler set to the following pressures: 1.25bar (1.00bar), 1.35bar (1.10bar), 1.45bar (1.20bar), the values in brackets are readings off the PID which shows roughly 0.25bar more for some reason. The next peak is the temperature taken with the probe embedded in the coffee puck at 1.5bar of boiler pressure, the last peak is the temperature taken with the probe embedded in the coffee puck at 1.25bar of boiler pressure.

For me the flushes are ultra hot, as this water will eventually make it's way to the coffee and it's pretty much at boiling point. The puck measurements sort of show this as well, although the recorded temperatures are slightly lower as the probe is lower and cover in material which takes away heat.

Or am I looking at this the wrong way altogether? the machine has been on for a few hours, idle for perhaps 2hrs.

T.


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## 4085

I always perform a short flush if left idle to kick start the thermosyphon. Try doing that then re-measure


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## dsc

I did do the three flushes with no extraction at the start, so surely that should've kicked the thermosyphon into action?

I've also stuck a probe on the group to check the temps during a shot, it goes all the way up to 90deg at 1.25bar of boiler pressure, which from what I've read should not happen (seen range 83-85 quoted on HB by Frans I think).

T.


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