After close to four years of flawless service, my QM Vetrano developed a huge leak out of the vacuum breaker on the boiler. I know I need a new O-ring or just a new breaker valve, but I wonder if anything else could be wrong before I order parts.

My Vetrano is plumbed to a filtered and regulated water supply. It's on a timer set to start warming up about 2 hours before I wake up. When I came upon the machine at the usual time, here's what I found:

1) Power on
2) Water everywhere, leaking profusely from the bottom of the case.
3) Boiler green-light on, but not hot.
4) Boiler pressure level in the red zone (over 2 bar).

Once I shut the power and water off (and cleaned up), I took the case cover off and turned back on the water and the vacuum breaker valve just let loose with water. Took out the valve and found the O-ring had disintegrated.

Is there anything in the above description to be concerned about, other than needing a new breaker?

Thanks for any weekend help. I'll call Chris' on Monday, but was wondering if I might get the machine back in order with a replaced o-ring this weekend.

Illyfex wrote:Water everywhere, leaking profusely from the bottom of the case... Boiler pressure level in the red zone (over 2 bar)... I took the case cover off and turned back on the water and the vacuum breaker valve just let loose with water.

What you describe sounds like the steam boiler overflowing because the water level sensor isn't shutting off the pump. That can happen if the water sensor fails to detect ground because it is covered with scale. See How to replace faulty water level sensor for details.

This is exactly what happened to mine at about the 3 year mark. It was in fact the water level probe, no scale on it though, just discolored. I was able to use some 400 grit sandpaper and get to work for another week, also recognizing that it was just the probe and nothing else. Also, also, supporting my habit until the probe came in from Chris

Thanks for the replies, guys.

I pulled the only water level sensor that I could find on the HX boiler. It was discolored a bit on the end (less than 1/4"), so I cleaned it and put it back. I also replaced the disintegrated O-ring on the breaker valve with one I found at Home Depot. Put everything back and pressured it up.

The breaker valve is sealing and there are no leaks. Only thing I notice is that the boiler pressure is a little higher than I'm used to seeing. It's cycling between 1,3 and 1,4 bars. I was used to 1,2 to 1,3. I should note that I completely disassembled the water sensor probe, so it may not be extending into the boiler at the same level. I think I'm going to order a new probe and breaker valve from CC, along with a boiler jacket (mine has crumbled), but right now, it looks like I might have espresso in the morning!

I would proceed very cautiously. For sure I agree that a corroded water level probe can increase the "normal" water level in the boiler . . . but NOT to the extent that you described.

The correct o-ring for the vacuum breaker valve (Italian designation OR102) is AS568-007, i.e. -007. The material is silicone. See this: O-rings & Copper Sealing Washers

Disconnect the pump electrically and lift the brew lever. What does the brew pressure portion of the gage read? I would recommend 2.50 bar. Your boiler fill solenoid valve will thank you.

What brand boiler fill solenoid valve do you have? If it is an OLAB, these have been more problematic than "normal". Replacing this valve is certainly doable but I would consider it something to proceed with patience in my pocket.

First of all IF it is the level probe the pump will be running. If the pump is running then it is an electrical failure. Could be the probe or the board. NOW IF your pump is NOT running and water is coming out the top of the vacuum breaker then your solenoid valve is stuck open and you have a mechanical failure. Some times a piece of scale gets stuck in the valve and it can't close all the way. When this happens water keeps going into the boiler and it has to go some where so it goes out the top of the vacuum breaker. To prove that your board is ok you can take the wire off the probe, the pump should start. Now touch and hold the end of the wire to the boiler or the frame of the machine. If the pump stops in a few seconds the board is good. If you put it back on the probe and the pump keeps running it is just the probe. IF you have cleaned the probe and and the pump is no longer running you now need to lower the level of water in the boiler. Simple way to do so is to open the hot water spigot and take out 6 ounces of water. Wait 5 seconds and if the pump does not come on that is good let the pressure build back up and take out 6 more ounces and wait to see if the pump comes on. Once the pump comes on it should only run a few second then shut off. You boiler level is now at the proper level. You can test to see if you repair worked by pulling 6 to 7 ounce out of the boiler and be sure your pump comes on, replaces what you pulled out and stops. If it keeps running look out it is going to come out of the vacuum breaker valve again and you repair was not a permanent fix.

Hey Chris - thanks for your reply! I'll definitely be calling your service department tomorrow, but for now, with only the replacement of the breaker valve o-ring, the machine is working exactly as it should. I've been pulling shots, steaming and using the hot water spigot mercilessly since yesterday and there are no leaks or strange behaviors by the machine. Left the cover off and power on overnight and was still fine this morning.

I think I'll just replace the valve as I have no idea what kind of O-ring I got from Home Depot. It could be silicone (good) or nitrile or some other synthetic rubber that is OK for faucets but not able to stand the heat of a boiler. I think I had mentioned that my original breaker valve o-ring was disintegrated -- to the point it wasn't even visible any longer. No way the bare piston could hold a seal.

Not sure, though, why the water didn't cut off when the problem first happened. Perhaps a piece of scale kept the solenoid valve open, but it's fine now (with no intervention on my part), so that's a head-scratcher.

I'll call service tomorrow. Maybe there are some things I should change out while I have the machine open. I know many of my electrical connectors are brittle from heat and my boiler jacket is crumbling. On weekdays, I cycle the machine on for four hours in the morning and four hours in the evening, and it's on 24/7 on weekends.

I know the tendency on boards is for people to post their problems, so I don't want to leave anyone with the impression the Vetrano is anything less than a great espresso machine. It gets heavy daily use in my home and I hope to keep it running for years to come.

OK, I declared victory too fast. My "fix" only worked for less than a day. Here's the problem as I see it now...

The machine heats to normal pressure, but the boiler pressure continues to rise after the heater shuts off, it essentially is rising to the point where it equals my water pressure. If I shut off the water and drain off a little water from the hot water dispenser, the pressure drops and won't go above normal 1,2-1,3 bar.

SO, I'm back where I started. For example, with the machine turned off and ice cold (the breaker valve plunger not seated), when I turn back on the water pressure, the water just pours out the open breaker valve, so it seems something is staying open in my fill solenoid maybe??? It's a Parker, BTW. If the solenoid valve is the culprit, should it be replaced or is cleaning an option?

Thanks.

Syphon water out of the boiler after removing the tubing heading towards the hot water wand. It would syphon fast but not 100% by fitting some hardware store tubing OVER the exposed threading at the boiler end. It would go slow but close to 100% by fitting some tubing INSIDE of the hot water tube extending into the boiler.

Clean valve cylinder assembly and piston in white vinegar for 45 minutes. It is worth a try.

Yep, I'm thinking this is my problem (valve is Parker)...