Post By noidle22
Faema E98 / La Cimbali Junior Troubleshooting - Boiler level rising / filling
I have acquired an unloved Faema E98 tank model (same as a Cimbali Junior) that I am fixing and cleaning up. I'm having an issue with the level of water in the boiler. When I am pulling a shot or backflushing, water seems to flow into the boiler as the boiler level rises.
The machine is a manual fill machine that has a button on the front which when pressed activates the pump and a solenoid.
Initial thoughts are that it could be:
- the solenoid failing to seal
- a crack in the HX (really hope not)
I can hear the click of the solenoid activating and I also took it apart when I was descaling the boiler. There was no obvious obstruction in the valve.
I've tried removing the electromagnet from the valve and pressed the boiler fill. The boiler still fills, albeit much more slowly.
Ive also noticed that the machine requires a rather long cooling flush - much longer than most other machines I've used. I've reduced the boiler pressure from about 1.3 to just over 1 bar.
So my questions are:
Could the boiler fill issue be anything other than a faulty solenoid or a cracked HX?
At first thought it seems like it is probably the solenoid, but im suprised considering it seemed fine inside. Could it still be the HX as the group solenoid is after the HX in the direction of flow?
Does the machine running hot provide any indication about the HX or is that pretty normal for this machine?
What boiler pressure do you guys who have this machine run at?
Many thanks for your help! Let me know if there is any more info required for trouble shooting.
Yes they run hot. Around 100ml of flush required after being idle for a while to stop the hissing and spitting from the group.
This may not apply to your machine. I had a similar problem with a HX Rocket Premium. On this model there is a solenoid just after the pump. The purpose of this solenoid is to differentiate between the high pressure required for extraction and the low pressure required to fill the boiler than has its level control. I found when I brewed the boiler would fill - the boiler pressure gauge looked good but all water no steam. We were able to service this solenoid and all is good now. This may help.
It shouldn't fill at all. The boiler fill solenoid is the only way for water to get into the boiler aside from, worst case as mentioned, a crack in the HX.
Originally Posted by adam4jc
My BFC Junior was recently exhibiting a similar problem but descaling the fill solenoid resolved it for me.
I would think your solenoid has just worn out. To keep the solenoid closed when inactive, the plunger has a spring behind it which applies the correct force to keep it closed. The spring may have worn out or the plunger seat has perished.
If it is a Parker or Lucifer solenoid (identified by the writing on the coil) then you can just replace the solenoid body and reuse the original coil.
Thanks everyone for the tips!
I finally had a bit of time to work on this again.
So i replaced the solenoid body (it's a lucifer 10 bar). I also took apart and descaled the over pressure valve that sits above the drip tray in the pipeline between the pump and the group head. This machine uses a vibe pump so there's no way that I can see to reduce the pressure short of having water released by the opv.
Anyway, reassembled everything, and went for a backflush... and up goes the boiler level.
Right. Damn. So i bit the bullet and removed the group head to get at the hx (the hx on this machine is removable as it is not a through pipe. Pulled it out and... it seems all intact. I've descaled the hx pipe overnight and I cannot even see a hairline crack!
So now I have no idea what is going on. A brand new fill solenoid, an intact hx pipe, and still water is entering the boiler under back pressure.
The only thing I can think of is that somehow my vibe pump is on steroids and is producing more pressure than the 10bar solenoid could handle. But even with the opv dripping water the boiler still fills - water has to be basically pouring out of the opv for the boiler level not to increase.
Im starting to be at a complete loss about what is going on! Anyone with some rebuild knowledge have any ideas about what is going on?
My next thought about troubleshooting (since I now have 2 solenoid valves) would be to block the fill pipe to the boiler with the old one, and attach the new one to the pump side, (so that they is a gap in the pipeline) and see if water leaks from the new solenoid when it is under pump pressure but closed valve. Thoughts?
I'm not a full bottle on the backflush mechanics. as far as I know, the back flush just makes water dump out the opv. If so..
Unplug the line between the fill solonoid and the boiler (after the fill solonoid). If its leaking, it will be noticeably coming out the fill pipe- when you back flush.
Or...you said you can remove the hx. So remove it and then back flush. It seems it would then be under pressure and show any leaks.
I don't know what things would need to be over ridden in order to make the pump operate without a hot boiler. Maybe wire up another pump with its own power supply. Or put pressure in by some other method. I think 100psi will be enough to show up your leak. How you get this is up to you...
You need to test your system under pressure, and maybe under heat also (in the case of the hx if just pressure shows no faults).
I don't know if its any use but...kerosene is way more viscous than water. If you removed and filled the hx with kero, it would leak like a sieve out of a crack that won't pass water. I have no idea how you would get the kero taste out of the pipe later.
I use kero to leak test cylinder heads. So taste is no issue there.
You are on right track with your trouble shooting. Just need to test under operating pressure now.
I have almost no experience with coffee machine fixing. But the issues and troubleshooting techniques are the same as every other machine once you know the systems employed. Isolate and test under operating conditions.
Recheck the HX. Under heat & Pressure. It could have a microscopic / pin hole size from corrosion .
I would take plenty of pics / drawings ...then fully disassemble, clean, descale and inspect components.
Lay em out in synch and that will help you diagnose the brew cycle flow path.
There is a manual held online here for the Faema E98 ....IIRC
Thanks for help.
Finally changed the HX pipe and the problem is fixed!
Thankfully the part was only $33 from the melb distributor + a couple of seals and the postage. So I'm pleased with that.
Unfortunately, im having the common problem that seems to come up with this model where the group handle has to be locked in super hard to avoid water leaking from the top of the group head =(.
Good work on fixing the issue!!
Re PF not sealing, firstly ensure collar is secured with all three bolts and that the seating area of the group seal is clean, and that you are using the correct conical group seal. remove collar, remove group seal, clean any gunk in collar and group where collar sits and group seal sits. Replace collar and gradually tighten all three bolts sequentially in increments. Insert new conical group seal. enjoy sealed group!
I have found even with nominal use the seals go hard in a 6 months and it taked a firmer lock in to prevent leaking. Also, if you brew pressure is set high it will encourage the leaking.
The group/collar design is simple and very robust. never had an issue if the above is followed.
Thanks Artman. I have tried as best I can to follow these instructions but have found the group head still needs to be locked in quite significantly harder than other commercial machines I have used to prevent leakage out the top. I thought the issue might be that the collar is off centre and so I have tried to be very careful when attaching but have still had issues. I have now changed to the flat (rather than conical) seal that is also available and this has improved things slightly (I'm guessing that the force is applied more directly vertically due to the flat surface which has improved the seal, however its still a bit of a pain.
With regards to brew pressure, I assume the OPV that dumps into the drip tray the only way to adjust the pressure on this vibe pump machine. I have adjusted to where I think it should be as best I can by comparing to another machine (same bean, same grind, same dose -> same extraction) but obviously without a pressure gauge this is pretty hit and miss. Next on the list of purchases!
Thanks for help
Not quite the correct sequence - the group seal is fitted to the head and THEN the collar is fitted -if you put the seal in with the collar in place it is very hard to get it seated correctly and it will almost certainly leak no matter how carefully you fit the seal.
Originally Posted by artman
(....and I know this well because in my early days as an espresso machine tech I was sent to service a 2 group Cimbali but hadn't been told the collar was a removable part, and the machine had plastic covers that hid the collar bolts. I fitted and refitted the new group seals several times without removing the collars and the just would't seal, until I rang my boss, asked him what I was doing wrong and was told about removing the collars).
Yes spot on, my error.
Originally Posted by MorganGT
If the seating surfaces are clean (sometimes can require a scrub) and the conical bolts on the collar are evenly and gradually tightened I cant see why it should leak. Its a robust and quite simple design.
Interesting you are getting better success with the flat seal rather than conical. My experience was the opposite.