Just purchased a PVE and I think coffee is refluxing into the boiler. I plan on changing the gaskets and have obtained the tool. Prior to changing I want to make sure the boiler is coffee residue free but I've heard that cafiza and espresso machine internals is a bad combination. Any recommendations?

Hi,
If you're changing the seals, then removing the element will give you access to the boiler, which would allow you to clean and scrub thoroughly.

I was hoping not to do a complete tear down but rather just change the piston seals.

Other than a complete tear down fill, slosh, dump, repeat. You can use a long handled bottle brush if needed, perhaps a little dish soap with thorough rinsing of boiling hot water.

Luckily the machine is small enough you can give it a good shake and dump it upside down without trouble.

Which solvent would you recommend? Or would you just use boiling water?

If you do a descale with citric acid/vinegar or some other solution you shouldn't really need detergent. As the minerals dissolve the coffee will likely float free.

It sounds like a problem I had. I stripped that thing down to every piece and cleaned it well as well as changed the piston gaskets (a real pain since it's spring loaded.) The heating element burned out when I poured cold water over hot coil (my fault) so I replaced that too with a new one. That also means it wasn't a dirty heating element.

I could never solve the problem.

After pulling multiple shots my boiler water would turn darker. It did not seem to affect flavor much but I did notice it. For some reason it seemed coffee found it's way into the boiler from the group ???????

It wasn't a big deal since I could aways easily dump the water out and replace it. I learned to live with it and it was not a bad machine.

If your piston seals are new, fit right and installed correctly, adequately lubricated with something like Dow 111, and everything is working right you shouldn't get any grinds into the boiler.

Having said that my La Pavoni had the same problem originally. Very limited, but it did have that issue. The group wall was rough so that you could visually see and feel ridges and I think it was trapping coffee particles along the wall allowing the seals to pass over and flush it back into the boiler. I addressed that issue by getting a 3-way brake honing tool at the auto parts store, put 400grit sandpaper on each of the pads, mounted it into the drill press and smoothed out the group bore. Don't need it 100% glass smooth, but you can't feel ridges on my group wall anymore. Work like that needs to be done slowly, and with constant checking so you don't over sand the hole.

FWIW, I've found that using just a touch more lube than you think you should use prolongs the life of the seals. My first round of seals after I got my Export only lasted about three months. I used a little more Dow on the second set and they have been holding on for almost a year.

I've not had any coffee in the boiler. When mine failed, I had water shooting out of the air vent on the back of the group.

Maybe your boiler pressure is set so low that it can't hold back the shot in the first microsecond of the pull before the seal covers up the hole leading to the boiler?

All good advice. I need to pick up some new seals and hopefully get to it soon. I definitely think it's hurting on lube. I purchased the service tool (a fool and his money...) so I'm hoping getting the piston out should be easier. I'll definitely feel for rough areas. Still make great coffee but I'm just annoyed that coffee is where no coffee should be.

Thanks for all the advice!