# Eric e61 temperature help.



## Dylan (Dec 5, 2011)

So, basically I just installed erics e61 and my machine is behaving somewhat differently to eric's instructions.

Its a VBM Domobar Super, a machine that Eric actually specifically picks out as needing very little flushing...

However my brew temp after the machine has been idle for a while is 101deg C and when flushing it will remain this high for a long time, over a minute of flushing is required to observe a drop in temp which is I assume how long it is taking for the full HX pipe within the boiler to be emptied.

The boiler is set to reach about 1.2bar, and although I dont fully understand false pressure and the like yet it will variously drop below 1 bar (opening and closing the steam will cause the heat to come on and rise, over about 5 seconds, to 1.2bar) and up to about 1.4bar. I dont understand this to be a particularly high boiler pressure and therefore temp?

I am going to experiment now with dropping the boiler pressure and see how the temp responds, if I get that right I hope the machine is going to require very little flushing, as it stays at a rock solid 101deg during my aforementioned flushing tests.


----------



## Dylan (Dec 5, 2011)

Just read

http://coffeegeek.com/forums/espresso/machines/2280

And now realising maybe I do in fact just have too high boiler pressure.


----------



## Dylan (Dec 5, 2011)

Just reduced the boiler pressure, it's now reading 0.7bar. Still getting 101dec C on the thermometer


----------



## urbanbumpkin (Jan 30, 2013)

Hi Dylan

When I used it on my HD the up to temp idle temp used to be 101c. I'd do a 5-6 sec flush wait for 2-3 mins (this was when I was weighing beans, grinding tamping) by then the temp used to have dropped to 95-95c on the Eric's. This was when I used to pull the shot.


----------



## Dylan (Dec 5, 2011)

I was a little hasty I think, I hadn't let the machine idle for long enough before testing the lower pressure. With the reduced boiler pressure (.5-.7) my group idle temp has been slowly dropping, and now reads about 87, and increases over about 8 seconds to 97deg. The group will then slowly drop back down again.

So is this an at all normal routine? I would be flushing the group not to cool it but to heat it up...?

This could be something to do with a thermosyphon restrictor eric mentiones in his instructions... is it the same kind of thing that is meant to eliminate the flush as in Fracino machines?

Edit: after this latest test, the group is idling at around 93deg.


----------



## Dylan (Dec 5, 2011)

Frustratingly, it seems that the temperature does not land in the same place every time, sometimes it seems to idle at around 92 and then the brew temp over the next minute will be 97, then it seems to settle at 96 and then the brew temp will be 100...

This may take some experimenting to learn what exactly is going on :/


----------



## Milanski (Oct 10, 2013)

I've just installed mine and been idle for 50 mins. I'm at 107.5c...

I hope I haven't paid £80 for a can of worms!


----------



## jeebsy (May 5, 2013)

Milanski said:


> I've just installed mine and been idle for 50 mins. I'm at 107.5c...
> 
> I hope I haven't paid £80 for a can of worms!


I asked xpenno what he thought about his and the advice was don't get one, it's better not knowing what goes on...


----------



## Dylan (Dec 5, 2011)

Milanski said:


> I've just installed mine and been idle for 50 mins. I'm at 107.5c...
> 
> I hope I haven't paid £80 for a can of worms!


During extraction or at idle?


----------



## Milanski (Oct 10, 2013)

Idle. I'm about to experiment now it's been on an hour.

Will report back.


----------



## Dylan (Dec 5, 2011)

Interestingly, my boiler cycling between .5 and .8 is the lowest my pstat will go... and this seems to be resulting in extractions at about 100, which is too hot... something cant be right here.


----------



## Dylan (Dec 5, 2011)

I keep reading that the Domobar Super does not need a cooling flush... which makes this even more confusing to me.


----------



## Dylan (Dec 5, 2011)

Could someone do me a favour and pull just water through their group for exactly 20 seconds and tell me the weight... I'm investigating a line of thought which involves wether the flow rate through my HX is sufficient.

Oh and on a vibratory pump


----------



## Dylan (Dec 5, 2011)

I found the data sheet for my vibratory pump which has this here:










It's one of the 70w models, all of which are about 40l/h flow rate, this translates to a flow rate of 666ml/m, my machine is outputting a measly 120ml/m.

So I think I may have a blockage somewhere and its too slow to allow the HX to operate properly. Bit of a bummer as it means I need to take my machine apart again -_-.

Do let me know if I have made a mistake.


----------



## Milanski (Oct 10, 2013)

Ok so 107c would be the long idle temp.

10-15min idle is at around 100c.

Pulling a mug-full of water (my normal flush amount) only takes me down to about 95c so I have to pull a pan's worth of water to get me down further.

Soon as I pull the shot though, the temp jumps to over 100c and more or less stays there for the duration of the shot.

Looks like I'd have to pull most of the tank through to get the temp to drop low enough (Eric suggests 85c) so I could prep and pull at around 91 so it jumps up to 96c giving me 93c at the puck!

Hmm...


----------



## Milanski (Oct 10, 2013)

Dylan said:


> So I think I may have a blockage somewhere and its too slow to allow the HX to operate properly. Bit of a bummer as it means I need to take my machine apart again -_-.


Def not a scale issue?


----------



## Dylan (Dec 5, 2011)

More than likely, I descaled all the pipes and the boiler and group and everything but scale is the likely culprit.

With regard to yours what is your boiler pressure set at?

On my other machine, a Expobar Office Pulsar I get around 400ml/m, so I am fairly sure now the VBM has got a blockage somewhere.


----------



## Milanski (Oct 10, 2013)

I'm at between 1 and 1.25 bar


----------



## El carajillo (Mar 16, 2013)

Dylan , could your P/ stat be sticking ? / how old is it ? / Try winding it up and down to see if there is any improvement .


----------



## bronc (Dec 10, 2012)

~200ml in 20 sec. My machine has an Ulka EP5 pump.


----------



## Dylan (Dec 5, 2011)

El carajillo said:


> Dylan , could your P/ stat be sticking ? / how old is it ? / Try winding it up and down to see if there is any improvement .


Changing it makes a clear difference in the boiler pressure, and it always seems to cycle through about .4 bar. So my guess is that is working ok.

I have descaler in the HX system at the moment, I'm hoping that will improve the flow rate.


----------



## Dylan (Dec 5, 2011)

After descaling I checked again and got about 360ml/m out of the group, still not good enough (actually suspect this is the same as before, as I waited until the first drops appeared this time). I then detached the pump directly from the pipework and checked the flow rate and this was only giving me 450ml/m, still well short of the 580ml/m the pump is rated at.

So... my line of thought now is to wonder if the Gicar has somehow been modified to reduce the flow of the pump as it was intended to be mains fed... Is this something that happens?

@espressotechno @DaveC

Its a brand new pump, btw.

Edit...

Just realised its actually not the same pump exactly.

Old model was 1106PAALM1N

New model is 1106PAALM1E000

Edit: just tested the old one and its flow rate is very similar, so don't think I need to be too worried about the difference in model number.

Edit: Tested with a multimeter the machine is delivering the full 240v to the pump, so my thinking on the Gicar having an influence must be wrong.


----------



## espressotechno (Apr 11, 2011)

What's the Gicar ECU code number ?


----------



## Dylan (Dec 5, 2011)

Gicar 9.1.23.10 01 (if thats the right number)

I just connected this up to the mains, and low and behold I get a 'normal' flow rate of 600ml/m. So I'm guessing something about the machine is designed for mains supply.

Which is a bugger, as I was hoping to tank feed it :/

I'm guessing its the pump that is meant to be mains fed, there is no flow restrictor and it is outputting a low flow directly from the pump. Mains fed is not an option in the place I'm moving to in a couple of months... would it be possible to just swap in an Ulka pump or something like that?


----------



## espressotechno (Apr 11, 2011)

Your Gicar ECU is a basic water level control board, so won't have any programming to distinguish between mains & tank water pressures.

Fitting a Flo-Jet pump will boost the tank pressure.....


----------



## Dylan (Dec 5, 2011)

espressotechno said:


> Your Gicar ECU is a basic water level control board, so won't have any programming to distinguish between mains & tank water pressures.
> 
> Fitting a Flo-Jet pump will boost the tank pressure.....


Thanks for the info, thats good to know.

So I think the last thing must be the pump, I dont really understand it as there is no mention of the pumps needing mains pressure in the datasheet but it pumps at the same level as my other machine and the post from bronc above as soon as you add mains, I know mains has a varying pressure but its the only thing I can think of.

It would be significantly cheaper to just buy another pump, like an Ulka, do you think it is a fair assumption to think this will solve the problem?


----------



## bronc (Dec 10, 2012)

Your problem is that the temperature of the water that sits in the E61 grouphead is too hot, right? Then I don't think the pump has anything to do with the temperature in the grouphead. Here is a video about how an E61 works:


----------



## Dylan (Dec 5, 2011)

bronc said:


> Your problem is that the temperature of the water that sits in the E61 grouphead is too hot, right? Then I don't think the pump has anything to do with the temperature in the grouphead. Here is a video about how an E61 works:


Thanks for the link but I know how an e61 works. The water that sits in the HX and grouphead is naturally too hot for coffee, as its surrounded by superheated water. A flush ejects this superheated water, if you look at a HX boiler the HX tube goes in from the bottom, pushing the water up through the pipes and into the group.

My problem is that it take 1min+ to flush the HX water down to 90ish deg, a slow pump makes perfect sense in this scenario, the quicker the water from the pump gets into the HX, the quicker the HX will cool down.


----------



## jeebsy (May 5, 2013)

Does pump pressure affect flow rate?

/doesn't matter, vibe pump


----------



## bronc (Dec 10, 2012)

Ah, I see.

To be honest, my experience with vibe pumps is that they either work or not. Do you have a way to measure the pressure? I'm thinking that if the pump can put out 9-10 bars of pressure after the OPV, it should be working fine. Find someone with an identical machine to give you a water output/minute measurement. Have you removed the E61 mushroom to check for scale?


----------



## Dylan (Dec 5, 2011)

Pump happily gets up to pressure, so no problems there, it just does it slower than I am used to.

Bronc that is also my experience, but it is admittedly limited. This machine was designed to be plumbed in and as soon as you do it pumps at a 'normal' rate. I tested the voltage to the pump and it is correct, unless the frequency can change its behavior (as I haven't checked this) then the pump is running 'as it should'. The pump is brand new.

The machine had a full strip down and descale. But even if this weren't the case I have tested the flow rate directly from the pump and it is still half what it should be.

The VBM Domobar Super is not a particularly common machine, so finding someone else with it will be dififcult.


----------



## bronc (Dec 10, 2012)

Try http://www.home-barista.com and http://www.coffeegeek.com if you can't find anyone with a VBM here.

EDIT: Does your machine have a flow restrictor in the HX?


----------



## Dylan (Dec 5, 2011)

For the moment its a low priority.

Even if I find someone with the same machine, it wont be a plumbed in machine that they are running from a tank. If its a tank fed machine it probably wont have the same pump (Ulka pumps are more common on this machine) so the test will be different. In addition to this the information wouldnt get me anywhere.

At the lowest the Pstat will go the water is too hot and takes a HUGE flush to bring down to temp. This means the machine is operating too hot for any reasonable scenario it may be used in. Something has to be awry.


----------



## jeebsy (May 5, 2013)

The HX pipes and thermosyphon can't hold that much water?


----------



## Dylan (Dec 5, 2011)

jeebsy said:


> The HX pipes and thermosyphon can't hold that much water?


I'm estimating here as it has been several months since I had it apart, but the HX pipe inside the boiler is maybe and inch wide by 3-4 inches high. Enough to need a good flow to eject it in a timely manner.

If the temp is taking 1min


----------



## El carajillo (Mar 16, 2013)

Dylan, could you rig up a temporary supply to your kitchen tap / washing M/ch point , just to check if it is the lack of mains pressure / flow volume ?

If you have the mains feed pipe for the cost of a fitting you could possibly use the end of W/ mch hose joined to the C / M/ch hose


----------



## Dylan (Dec 5, 2011)

Yup, I did that, post #24.

That confirmed that with mains pressure I get regular flow, however there are no restrictors before the pump and the datasheet for the pump says nothing about needing mains pressure, which is odd. I'm going to see if my multimeter can read frequency and see if this (from the Gicar) matches the rating for the pump.

This lead to the question could I just install an Ulka pump and still feed it from a tank to get the flow back up to normal... my guess to that one is yes, so long as I get one rated the same as the fluid-o-tech.

I'm moving in with my Girlfriend soon and drilling holes through her cupboards or walls to get a feed from the sink is an absolute no go for the foreseeable future. So I need an alternative solution, preferably not a bulky £150 flojet I'll have to find somewhere to mount.


----------



## bronc (Dec 10, 2012)

Any progress?


----------



## Dylan (Dec 5, 2011)

No, probably wont be any until the weekend, and even then all I will be able to do is try and figure out if the pump is being run 'under-capacity'.

The fact that it runs correctly with mains pressure, and the pump has half the flow rate it should even when completely isolated without mains suggests to me that this is exactly how it is supposed to operate (plumbed in, as this is its design).

If anyone has a spare pump knocking about I can test my theory with that would be super, otherwise I think I'll just buy one on ebay, not a huge outlay.


----------



## Dylan (Dec 5, 2011)

So the pump is getting the correct frequency of 50hz and the correct voltage of 240v, there are no blockages to the pipework before the pump so I cannot understand why the pump only delivers half its advertised flow rate when dispersing directly from the pump. There is nothing on its datasheet about it needing pressure to operate at its advertised flow rate.

But the pump is the only weak link I can think of, so as a new ulka pump can be had for £12 I'm going to give that a go I think, I'm out of other ideas.


----------



## Dylan (Dec 5, 2011)

Update on this -

Bought an Ulka EX5 pump, fitted it and now the flow rate is much better, roughly 220ml in 20 seconds, so 660ml/m which is exactly where it should be.

I can only assume one of two things, that the pump in the machine needs mains pressure or the pump I bought off of ebay was faulty with low pressure. Either way the Ulka doesn't seem too much noisier and its for use at home so the higher quality fluid-o-tech wont ever be tested to its commercial standard anyhow.

Now I can get back to seeing if the flush is more normal...


----------



## Milanski (Oct 10, 2013)

My brew head seems to be happiest at 100 degrees.

Have to flush ludicrous amounts of water to get it down to 93 then coffee is sour/cool compared to the 93 set on PID of the Silvia.

What's everyone else's experience with this so far??


----------



## marcuswar (Aug 19, 2013)

You shouldn't be flushing down to 93 ! The eric thermometer shows you the temp of the water in the path to the puck not at the puck itself. I flush down to 98c from 100c idle (about 6 secs from the eaterdance probably 6 or 7oz of water) and the give it about 15secs to recover back to 98c as the temperature will immeadiatly rise and then fall after flushing. Once the shot is being pulled the temp drops to about 95-96c on the probe which should give a brew temperature of around 93c at the puck.


----------



## Dylan (Dec 5, 2011)

marcuswar said:


> You shouldn't be flushing down to 93 ! The eric thermometer shows you the temp of the water in the path to the puck not at the puck itself. I flush down to 98c from 100c idle (about 6 secs from the eaterdance probably 6 or 7oz of water) and the give it about 15secs to recover back to 98c as the temperature will immeadiatly rise and then fall after flushing. Once the shot is being pulled the temp drops to about 95-96c on the probe which should give a brew temperature of around 93c at the puck.


According to Eric's instructions (one method at least), you should flush down to this temp, before allowing it to recover.

You shouldn't pull a shot at that temp certainly, but flushing down that far is only so you can pull during the recovery. It is important to stress how different different machines are however.



> In the flush-n-wait method, you are flushing a sufficient quantity of water through the
> 
> grouphead to cool it down a few degrees BELOW desired brew temperature. Using the
> 
> ...


----------



## Milanski (Oct 10, 2013)

My machine idles at 107.5 and a mug-full of water (about 25s) gets me down to about 103 and then it sits at about 100c for a while until I pull my shot (1 min max).

So should I be flushing enough water to aim for a rebound, shot-pull temp of 98c?


----------

