[Paolo_Cortese]

To find out if it's normal, presumably we can compare with experience with owner of an izzo leva which uses the same group (although it doesn't have the heater cartridges). @TomR has one - Tom do you get some water leaking through the group as it gets up to temperature?

the izzo group doesn't have a water chamber

 

[danielpugh]

the izzo group doesn't have a water chamber

That's a shame. 20ml doesn't sound like a lot. Would be good to have a benchmark as to whether can be eliminated or not. If not then can forget and vice-versa.

 

[DavecUK]

what Paolo is saying, which I didn't want to get into (because it helps any competition)...the group used in the Evo is a little bit special inside, it supports the group heaters but has a semi saturated design. When the group heats the water will increase in volume within the internal chambers and a small amount of water will flow out of the water injection hole.

It can't be eliminated and you wouldn't want to as this is what makes the group more effective at controlling temperature and spreading heat around the group. It's not a problem unless it continues when the group has heated up.

P.S. The expanding water also needs somewhere to go...or it can damage the inlet valve.

 

[Like Medium Strong Coffee]

It's not a problem unless it continues when the group has heated up

Thanks Dave for simplifying it for non-technical people like me. 😊

 

[danielpugh]

Cool - I'm happy with an "it's normal, don't worry about it"

 

[TomR]

the izzo group doesn't have a water chamber

And it doesn't leak

although im usually asleep when its warming up

 

[Stevebee]

And it doesn't leak

and the boiler doesn't fill either 🤣

 

[DavecUK]

and the boiler doesn't fill either ????

 

[TomR]

*Sad face* 😰

*thumbs up*😂😂

still, it's in my house, not in Italy still…

riposte!

also: tried the ims screen

Does not seem to change extraction but stays cleaner maybe

happy pulling everyone

 

[Paolo5]

My concern was that for all 4 legs to have been 'removed' with the tender care of DHS, that my machine may have sustained some internal damage. I am not worried about the 20ml leaking...especially if it is normal behaviour for this group.

The shots that I am getting from my Evo are superb! I must have made nealy 20 shots so far...and the nearest machines that I can name that can deliver the depth of flavours and crema from the beans that I roast on my Dalian are the Vesuvius and the vintage Brugnetti Aurora....high praise indeed! And I haven't experimented with declining temperature shots or manoeuvred the lever during a shot...just let the machine do its thing.

 

[The Systemic Kid]

@Paolo5 what temperatures are you using?

 

[Paolo5]

I have the group heaters set at 96.5C (to compensate for the Bplus screen that I am using) and the water temperature set to 96C. I haven't felt the desire to change anything yet...but isn't it great knowing that I can.... :classic_biggrin:

 

[Paolo5]

what Paolo is saying, which I didn't want to get into (because it helps any competition)...the group used in the Evo is a little bit special inside, it supports the group heaters but has a semi saturated design. When the group heats the water will increase in volume within the internal chambers and a small amount of water will flow out of the water injection hole.

It can't be eliminated and you wouldn't want to as this is what makes the group more effective at controlling temperature and spreading heat around the group. It's not a problem unless it continues when the group has heated up.

P.S. The expanding water also needs somewhere to go...or it can damage the inlet valve.

Thanks, Dave.

Just so that I have it clearly in my head...you saying that this expansion and 20ml of initial dripping is part of the modified group's design and ALL Evo's do this.

Is that correct?

 

[Stevebee]

I have the group heaters set at 96.5C (to compensate for the Bplus screen that I am using) and the water temperature set to 96C. I haven't felt the desire to change anything yet...but isn't it great knowing that I can.... :classic_biggrin:

There should be 8-10c between the brew boiler setting and the group heaters. This is because the water loses about that much on it's travel to the group. On your settings the water temp when it hits the group will be way below what you want. Not sure the elements in the group can get the temp back up for the shot but the system won't be in balance how it is supposed to work.

As an aside, BPlus recommends a 2/3c higher brew temp but only for the 1st shot as after that the temp effect is negligible as it has warmed up

 

[Paolo5]

Thanks Steve...I have read that.

I just made a shot on the settings that I have had since I set the machine up and it was great! No sourness that one would exprect from too-low an extraction temperature.

I'm duly caffeinated now but will set the brew boiler temp. to 105C and try it tomorrow.

 

[MW11]

I have the group heaters set at 96.5C (to compensate for the Bplus screen that I am using) and the water temperature set to 96C. I haven't felt the desire to change anything yet...but isn't it great knowing that I can.... :classic_biggrin:

I have the Bplus dispersion screen too 😂 ok you are the official Evo whisperer! Tell us everything you do and share recipes (Pi time…etc)

 

[Denis S]

The temperature thing is so 1990. Can you believe there are people who think a steady temp line w/o dropping more of 0.5C is good for making espresso? saturated group temp stability.

Temperature is related to the compounds you want to extract. Lately, the decent club is playing with ultra low temps on ultra light roasts and the results are insane good.

Shot pulled at 89 C injected preinfusion temp with a drop to 84C final brewing temp (on purpose). Light roasted ethiopia natural on Loring, rested and frozen. Taste is mango and tropical fruit jogurt ice cream, bergamot.

Temperature is a nice experimentation thing, and i'm glad I can tweak it on Leva, I just hope there is no software limitation to go under 90-88C like some other machines have it (DC I believe).

Speaking of extraction, the above shot was 18g in/46.2g out with over 25% EY (at low temp).

 

[Like Medium Strong Coffee]

There should be 8-10c between the brew boiler setting and the group heaters

@Steevdee and @DavecUK I have a question.

Although this is a recommended setting, wouldn't the group heater be able to quickly heat and maintain the temperature at the set level ? I remember Dave saying it takes only a few seconds. But, here the temperature loss would be substantial.

The water would have already hit the puck 8-10C lower causing sourness. The group heater would have already corrected the temperature loss, minimising the sourness before a few drops fall on the cup. When the shot is pulled, the temperature loss may not be an issue anymore. @Paolo5 did not taste any sourness. Thx

 

[DavecUK]

@Like Medium Strong Coffee I guess it's up to each owners...I'd personally not set the group heaters to 96.5 and I would always want to compensate for the delta between the water leaving the brew boiler and entering the group. So I would probably aim for something more like 95 group heater, if I wanted it really really hot...and 102 or 103 brew boiler.

Of course I can't help people with temps any more because my test bed used an ex commercial scrap group and only one of the heaters fitted well...(6 years ago the heaters didn't have a good fit in the groups)...different fitment and the heater that fitted badly on my very old group burnt out after a few days.

I have been waiting for an up-to-date new group bottom half, with the modern heater fitment and also because my water valve also leaks badly. However ACS has never sent one...it would also be a major ballache for me to fit in the Alpha because of the way it is inside.

The Alpha was simply a proof of concept and is a much poorer machine in every respect than the production machines....effectively it's worth nothing..

 

[Like Medium Strong Coffee]

@DavecUK Many thanks to you, Paolo and his team for designing and producing the awesomely beautiful machine. We will always look up to you for expert guidance, advise, fix recommendations and many more. I am sure the ACS will send what is required to keep the test bed up to date. It is also in their interests as it will also serve them well in the future. I think, you may most probably require a production grade test machine to plan any significant enhancements. IMHO, this is what the ACS could / should do, without which it will be difficult to figure out what works or otherwise, tweaks, and so on. 😊

Edit: Sorry, I left out the manual, which isn't an easy task and helps us massively. Thx @SL01 for pointing this out.