# Help please. Diagnosing problem with dialing in.



## MikeHag (Mar 13, 2011)

With my new machine now installed at home (a commercial Faema Enova 2 group) I initially had some great shots with some Lusty Glaze. But I'm really struggling at the moment. The shots are blonding early, lifeless, tasteless, thin. I'm in unfamiliar territory here and need some more brainpower to identify possible root causes









I do have new burrs on the Super Jolly, which have seen about 2kg through them. Maybe the burrs need more seasoning? Could that cause blonding?

Also, I know that yellowing comes from low brew temperatures, but I have a suspicion that I may have the groups set a little too high rather than too low. (I'm not getting credible readings at the moment with my shitty k-type thermocouple, so don't know the actual temperatures!) Are the symptoms listed above typical of overly hot temperatures? Overly hot isn't something I am accustomed to, or experienced with the Gaggia Classic, as the Classic tends to cool throughout the shot.

Any other ideas what this might be?


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## fatboyslim (Sep 29, 2011)

I would associate thin shots with very little crema with too a high temperature.

How much are you flushing through groups before pulling a shot? Have you tried both groups?

No idea whether brew water is heat exchanged or dedicated brew boiler on that machine but flushing always helps









Does it have a gauge for boiler pressure?


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## MikeHag (Mar 13, 2011)

There's plenty of crema, but not the right colour and consistency. I've tried short flushes and long flushes and haven't found a flush that helps yet. Pressure gauge is fine, boiler 1.1bar and group head at 9bar.


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## RolandG (Jul 25, 2010)

Always answer a question with a question









Are the shots running quickly?

Are you tasting any bitter/burnt notes?

What is the crema like?


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## MikeHag (Mar 13, 2011)

Both writing at the same time, Roland









I'm getting a little speeding up through the shot, which I suspect is the burrs (the beans are 10 days past roast). I've tightened up the grind to compensate but I'm not too happy with the thin flow that it's producing... don't think that's helping. Not really a burnt taste, just kinda boring. None of the chocolate. None of the sweetness. A crap black shot with yellow head, not the rich brown shot I've come to expect. Not bitter either, just very charmless. I've updosed, to no effect. Wanted to seek opinions before going further. Really annoyed with myself!


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## fatboyslim (Sep 29, 2011)

Do you have another grinder to try?

At least that would rule out your SJ.


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## RolandG (Jul 25, 2010)

off the top of my head, I'd suggest that higher temperature usually creates some bitterness, so it's unlikely to be that? (I also don't know much about overly high temp though!). Low temperature could cause issues like this, but the fact that it's suddenly changed suggests something breaking rather than flush routine or anything like that. Flat flavour and early blonding usually (in my experience anyway) indicate lack of extraction (too coarse grind or similar), but updosing would usually effect this.... At the same time, I'm dubious about the need to further season your burrs. I've heard a lot of theorising about seasoning, but no firm facts. So too many options







Try checking that the burrs are correctly seated and either try and use an alternate machine with that grinder, or alternate grinder with the Faema to confirm where the problem is.


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## MikeHag (Mar 13, 2011)

Thanks guys. Gonna try lower temp setting first, then a different grinder, then various other shit!


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## fatboyslim (Sep 29, 2011)

Make sure to report back so when I get my own Faema machine I'll know how to use it.

Emphasis on the *when* there and no if's!


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## jimbow (Oct 13, 2011)

Since the shots you liked, have you changed your flush routine, the length of time it is sat idle or the amount of time it is left after switching on? All of these could affect the brew water temperature on a HX machine (I am assuming your Faema is indeed a HX and not a double boiler).


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## MikeHag (Mar 13, 2011)

Yeah, HX. Haven't changed anything. Kept it clean. Same routine. Bit flummoxed thb.

Anyway, trying again at lower temp tonight.


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## jimbow (Oct 13, 2011)

I have found that flat and dull taste can sometimes be a sign of over extraction with some beans - San Jose red bourbon used to behave like this for me sometimes and used to also happen as the beans aged. Not sure whether it helps, but I used to get around this by up-dosing and/or backing off on the grind.


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## MikeHag (Mar 13, 2011)

After reducing the group temperature the issue seems to have been significantly improved. Caramels have returned, texture is better, everything is almost back to normal







I'll be tweaking more tomorrow.

I think perhaps the over-hot water must have been practically jet-washing the solids off the grinds rather than percolating & brewing... hence the apparent reduction in flavour, oils and sugars.

Great little learning experience for me.

By chance, does anyone have a Scace I could borrow to check the group temperatures?


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## jimbow (Oct 13, 2011)

Good news Mike. Out of interest how did you reduce the temperature at the group - longer cooling flush?


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## MikeHag (Mar 13, 2011)

The machine has a feature called a Thermal Balancing System. Take the top off, turn a numbered dial on each group (I reduced from 8 to 6), and supposedly by 10 mins later the temperature will have stabilised at the new setting. Pity there's no digital thermometer built in tho.


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## jimbow (Oct 13, 2011)

Ah thanks, sounds a bit like a flow restrictor valve. I imagine this would cool down the group by restricting, and slowing, the flow of the thermosyphon.


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## MikeHag (Mar 13, 2011)

Yeah, fancy name for a fairly standard feature I think! But it's a nice feature, for sure... as long as you don't have it set too hot


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## fatboyslim (Sep 29, 2011)

So I was right









Glad to see you resolved it.


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## MikeHag (Mar 13, 2011)

One other thing that was a slight revelation...

I already knew about the different taste receptors in different parts of the mouth/tongue... sweet, sour, salty, bitter etc. So anyway I've been using my new 25ml mini-beakers to capture single shots from the two spouts. The beakers are quite thin i.e. the diameter of the base is quite small, so when drinking from it you need to pucker your mouth a bit, and the espresso kind of only goes down the centre of your tongue and then down the throat. Very little flavour, very little joy. But if I poured it from the beaker and into a normal espresso cup (tulip shape), the cup encourages you to swill the espresso around your whole tongue. This seems to bring out much more sweetness and complexity from the espresso.

Seems pretty obvious, but not something I had previously related to the shape of the espresso vessel.


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## Outlaw333 (Dec 13, 2011)

The narrower vessel also affects your intake of aroma/flavour through your nose, as you will know, your tongue detects only sweet, salty, bitter, sour and umami, the rest is all decoded by the olfactory system, so detailed notes on flavour will be harder to detect. The larger the surface area of the coffee the more particles can be released, the same goes inside your mouth as the larger the pool over your tongue the more free aroma particles are to travel up the nasal cavity, as you said you are more inclined to swill the shot over your tongue when using a wider vessel. Without trying to push my preferences on you, I use these for espresso and find they help achive a clearer picture http://www.coffeehit.co.uk/white-ischia-espresso-cup-70ml-2-5oz/p928

Anyway, what i was going to say was, are you using a naked PF to help with diagnosis of these kind of issues and could it have anything to do with the huge size of the boiler for the reletively low turnover, which may have caused 'dead water' having been in there too long and recieving numerous heating and cooling cycles, i only thought of this as you said you got some good shots early on. You have actually debunked my theory anyway as it was temp related.

I'll go now!


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## MikeHag (Mar 13, 2011)

I'm going through about 20L of water a day thru the machine. 11L boiler. I do plan to do a complete flush weekly tho.

I'm not using a naked PF but tbh I was doubtful it wasn't distribution issue. But if I had one for this machine I'd have tried that too!

No, defo temperature. I've spent some time today graphing the hump of the brew water temperature over 30 seconds. Even with the temp much lower now, at the top of the hump it almost hits 94C, so I'm guessing it was well above that a few days ago, so this again confirms my suspicions.

My challenge now is to learn to manipulate the HX hump better... or get a PID for it!


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## Outlaw333 (Dec 13, 2011)

My local Boston Tea Party used to use Faema Machines, do you want me to see if I could get hold of one of their old Naked PFs for you?


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## MikeHag (Mar 13, 2011)

If they have some going to waste that might be good... Thanks! Haven't they just scrapped old equipment?


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## jimbow (Oct 13, 2011)

I remain sceptical over the use of a PID on a HX as the brew water is indirectly heated by the steam boiler. Having said that I have read people reporting successes doing just this. In this configuration, the PID measures the temperature of the brew water in the thermosyphon and heats the steam boiler accordingly. The downside is that steam pressure suffers dramatically as a result - the guys doing it reported average pressures in the steam boiler below 0.7 bar if I remember correctly.

I would be really interested in your methods for recording temperature at the group head and your results, I am in the process of doing this with my Cherub. I find it really interesting how the cooling flush and subsequent rebound time affect different parts of the temperature profile.

I would not worry too much about emptying the steam boiler as the water inside it is in a seperate circuit from the brew water and the two do not mix. The brew water is pumped through the HX and thermosyphon circuit which, depending upon the machine, will have a low volume and so should be fresh. This is one of the traditional arguments in favour of HX machines over double boiler machines. I tend to cycle the water in the steam boiler once a week through the hot water tap depending upon how much I am using the hot water tap and steaming wand.


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## MikeHag (Mar 13, 2011)

Aah, silly me, yes. I forgot that's how a HX works. I'm still getting used to commercial/prosumer innards.

Here's how I'm measuring brew water temperature






Its a method used by Dan Kehn of Home Barista. K-type thermocouple wire up a single spouted PF.

I'm videoing it then capturing the temperature per second from the vid, to put in a chart.

It's not perfect as it doesn't show brew temperature... just brew water temp.


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## Outlaw333 (Dec 13, 2011)

Yeah I would have thought so too but Lee (the guy I introduced you to on twitter the other day), Pulled out one of the regular Faema PFs a couple of weeks ago when we were chatting about the new La Spaz's, I would expect they might have a naked one lying around somewhere. I'm going in tomorrow so i'll ask, I have a funny feeling Lee has recently left but i'm pretty friendly with the other members of staff.


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