ACS Evo Leva Leaking Part

IridiumBlackberry

Hi all,

I recently plumbed in my ACS Leva, and after a week on vacation I came back to my machine short circuiting. I thought initially it was my plumbing on the water input but it turns out this other black part seems to be leaking. I’ve attached a video illustrating the problem when I turn the machine on.

What could be the problem? Is the input water pressure too high(but maybe that makes no sense as it fills the tank and not directly the machine?

Video Link:

Thank you for your help!

Cuprajake

thats the pressure switch, you will need to change it out, @LMSC had this recently.

IridiumBlackberry

thanks for the quick reply though! Where can I buy this?

IridiumBlackberry

Also was that just unlucky and random? Or did I do something wrong?

Cuprajake

whats your input pressure?

Cuprajake

its a ceme pressurestat, the number is on the side, perhaps @DavecUK has one knocking about, but other than that ask acs on email sales@mevsrl.net

IridiumBlackberry

I think around 6 bar… I’d have to measure it again. Maybe I’ll put a reducer back on and set it to 4 bar.

I found this one https://shop.schneider-berlin.de/en/Technical-accessories/Parts-for-steam-boilers/Pressure-switches-and-accessories/Pressure-switches-simple/PRESSURE-SWITCH-1-4-CEME-oxid.html

Seems to be orientated to businesses…

IridiumBlackberry

Ah actually this one seems to be right. The other has a limit of 10 bar rather than 6

https://shop.schneider-berlin.de/en/Technical-accessories/Parts-for-steam-boilers/Pressure-switches-and-accessories/Pressure-switches-simple/PRESSURE-SWITCH-1-4-CEME.html?force_sid=20hrang7l39aq11pljn4np4qqa32nuf6estej18632f3m3j1na40

DavecUK

IridiumBlackberry Ah actually this one seems to be right. The other has a limit of 10 bar rather than 6

That is the correct pressure stat 0.2-6 bar refers to the pressure range in which it will work, I believe burst pressure is 12 Bar (manufacturer stated), but I think that prolonged high pressure above 9 bar can cause them to fail earlier than that. In effect the casing separates, and then it leaks around the top rim.

When you change it, make absolutely sure your expansion valve in the Evo is set as low as it will function correctly to 6-7 bar…. There obviously needs to be some positive spring tension in the expansion valve for it to work correctly and not let by all the time..It’s possible the expansion valve is set too tight is allowing excess pressure to build up when old water enters the brew boiler and then expands on heating.

How old is the machine?

P.S. Inlet water pressure has nothing to do with it

Cuprajake

id say 6 bar is the limit, so could of killed the internal diaphragm.

id drop to 3 or 4 depending on what pressure you use.

LMSC

Based on the discussion, unless it is a line pressure related problem, the pressure stat requires replacing. I can’t see the video, though.

IridiumBlackberry

DavecUK When you change it, make absolutely sure your expansion valve in the Evo is set as low as it will function correctly to 6-7 bar…. There obviously needs to be some positive spring tension in the expansion valve for it to work correctly and not let by all the time..

What’s the expansion valve? Where is this located?

DavecUK

With the top removed from your machine, take a photo, paste it in and I will identify it for you. Or follow the tube back from the drip tray.

IridiumBlackberry

Yeah sure, here’s a pic.

DavecUK

marked with red arrow

IridiumBlackberry

Ok, sorry for the dumb question, but you’re referring to the gold brass object?

DavecUK

IridiumBlackberry Ok, sorry for the dumb question, but you’re referring to the gold brass object?

Yes, the right hand end screws out anticlockwise to lower spring tension on a sealing pad (and hence pressure), turn it clockwise and you increase pressure. This is for the hydraulic pressure cause by water expansion (by heating) when cold water enters a hot boiler. It’s why it’s called and expansion valve. Remove the hose first or you will damage it.

IridiumBlackberry Also would I not have to worry about the setting of this valve if I place a pressure reduce on the water inlet to the machine?

The water inlet only fills the internal tank and has nothing to do with the issue. For safety from general leaks, you may want to put a “proper” pressure reducing valve on the mains inlet. For the problem you have they are completely unrelated.

IridiumBlackberry

Also would I not have to worry about the setting of this valve if I place a pressure reduce on the water inlet to the machine?

IridiumBlackberry

Hey @DavecUK thanks for the detailed response! Much appreciated.

So just to recap, before I go to replace the pressure stat I need to make sure that the expansion valve is as loose as it will go? And before adjusting the expansion valve I should remove the tube connecting it?

Oh I missed your question around how old the machine was shipped around November December 2021.

DavecUK

IridiumBlackberry Oh I missed your question around how old the machine was shipped around November December 2021.

If it was direct from ACS, you have 2 years warranty…so should be good until November 2023. Let ACS know.

Which country are you in
Yes you have to remove the silicone tube or it will tear
No not as loose as it will go, there must be enough thread engagement and some positive spring pressure on the pad…if water pisses into the drip tray when preinfusing a shot, then it’s way too lose.

http://coffeetime.wdfiles.com/local--files/opv-over-pressure-valve/OPV_Valve.pdf