La Pavoni EPC-8 Suddenly Has Low Boiler Pressure

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mrbananas
Posts: 33
Joined: 8 years ago

#1: Post by mrbananas »

Hi folks,

This is a "new" EPC-8 Millenium Gen III I recently purchased via Ebay, and you folks have been nice enough to help me troubleshoot a leaky sleeve o-ring: La Pavoni EPC-8 Millenium / Gen III Leaking Through New Sleeve / O Ring

Just as I was starting to get the hang of pulling good shots, I've encountered a new problem: all of a sudden, the boiler can't build up enough pressure to steam or even pull much water through the group. The pressurestat green light turns on when I power on the machine, stays green and then shuts off after a while (much like before). However, The steam wand gives a mix of water and a little steam, and the group only gives me hot water after pumping a few times like when it's cold.

This started yesterday, and has been happening the last 3 times I've tried powering the machine up. Any ideas on where to look next for troubleshooting?

Thanks again folks! Eddy

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rpavlis
Posts: 1799
Joined: 12 years ago

#2: Post by rpavlis »

It is a good thing to have a pressure gauge of one kind or another with these machines. Some people install permanent ones on top of the sight gauge. Others use temporary gauges that they connect to the steam wand. I use a special boiler cap with a gauge on it that I made using a lathe. The gauge pressure should be on the order of 70 kPa or 0.7 bar.

For some reason your pressurestat is turning off too early. Weird things happen when the tubing leading to a pressurestat is blocked from scale. There may also be some other reasons for this type of malfunction. Perhaps there also is some problem with the thermal safety "fuse" or "reset". You could bypass this temporarily to see if it then function properly. If it work fine then replace the safety device, do not leave it by passed.

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mrbananas (original poster)
Posts: 33
Joined: 8 years ago

#3: Post by mrbananas (original poster) »

A pressure gauge set from ebay is already in the mail...

I assume the pressurestat tubing and the safety fuse are inside the base... I have a Torx security wrench set also in the mail...

We need teleporting technology so I can just have all that stuff right now!

mrbananas (original poster)
Posts: 33
Joined: 8 years ago

#4: Post by mrbananas (original poster) »

While I wait for tools to ship, you guys did, however, give me some better search terms that helped me hit some old threads relevant to my issue. Adding thermal fuse to my searches gave me this thread:

La Pavoni Pro: Help diagnosing a steam boiler pressure problem?

And from that thread I found this: http://www.francescoceccarelli.eu/La_Pa ... to_eng.htm

That thread is encouraging, as it sounds an awful lot like my problem. We'll see what I find when I'm able to get in there under the base...

mrbananas (original poster)
Posts: 33
Joined: 8 years ago

#5: Post by mrbananas (original poster) »

I bypassed the thermostat following Francesco's instructions and bingo, pressure is back. I'll be ordering a replacement thermostat from Stefano's shortly.

Thanks again for the pointers!

mrbananas (original poster)
Posts: 33
Joined: 8 years ago

#6: Post by mrbananas (original poster) »

Hi folks,

So I need some help here again... After having pulled a few shots without the thermostat in place, my pressurestat / boiler now seems to have stopped working altogether!

So when I flip the switch on, I get red light for power, but the green light never comes on now, and the water in the boiler does not heat up.

I tried checking all the wires and they all seem to be connected firmly, and they are all free of scale or any discernible gunk. Any ideas on what I can try next to debug this?

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hankbates
Posts: 446
Joined: 13 years ago

#7: Post by hankbates »

From here, I would proceed:
If you haven't removed and replaced all the wires from their posts, do that, and use a contact cleaner if any corrosion is seen.
Then, bypass the switch, they frequently fail. (Bypass each item in the circuit, except for the heating element, individually)
If this doesn't work, check the heating element with a suitable ohm meter.
Some people rescue dogs and cats, I like to rescue Livias…

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mrbananas (original poster)
Posts: 33
Joined: 8 years ago

#8: Post by mrbananas (original poster) »

Heating element checked out ok on a multimeter. Electrons flow between the 2 posts, but not from either post to ground. Pulled all the wires out of their posts, and I couldn't see any corrosion, everything looked pretty clean. I put the machine back together and it starts working again!

Only thing I can think of was that I noticed that the thermostat (the apparently broken one) is a little loose, and might have been touching the nut / screw that held it in place. I did spin it around and off that screw. I have its posts covered both ends of the same cable in a loop, but maybe I was creating a short the way it was precariously hanging out there...

I'm happy to have espresso back either way. Though it's probably time to install that replacement thermostat...