In the last few weeks, my Vetrano has started hissing continuously. I took the top and side covers off, and I can see a bit of steam coming from the pin/valve on top of the boiler. Jiggled it a bit with pliers, but it just does not seem to completely close.

Do these vacuum breaker valves go bad after a few years (I've had the machine 4-5 years) or need to be cleaned every now and then?

Sounds like the vacuum breaker needs cleaning or replacing. They tend to get covered in scale after a few years, and then they won't seal properly. You can unscrew the top of the valve and soak it in vinegar to clean it. That may be enough to get it to close. If that doesn't work, you can get a replacement from Chris' Coffee.

i think you can replace the o-ring that's in there with one from home depot or lowes. take it apart and find the o-ring then get the same one.

Thanks Beezer and RegulatorJohnson - I was able to take the valve off and clean it in a weak citric acid solution. That cleaned off a little bit of scale. I also had to replace the O-ring as it had really deteriorated. After those two changes - good as new.

Thanks so much for the advice!

-Steve

I'm having the same problem with my Vetrano. I heard continuous hissing, so I removed the outer shell and saw that steam was leaking from the vacuum breaker valve. I saw the advice in this thread to remove the valve, soak it in vinegar, and replace the o-ring. My problem is that I can't get it off! I tried to remove the valve by unscrewing it with a socket wrench, and it won't budge. Any advice would be much appreciated.

Thanks,
Josh

And you do realize that the vacuum breaker valve is "two-piece" ?


Piece 2 is likely sealed into the boiler with a sealant whereas the nut on the left SHOULD unscrew. You will definitely need to apply a counterhold to the boiler to avoid twisting things you shouldn't be. I would not suggest replacing the o-ring with a hardware store item EVEN THOUGH others have had success with that. Hardware store o-rings are NOT designed to handle the temps seen in this area.

Thanks for this helpful info, Eric. But I'm still having no luck getting the nut to unscrew. Can I apply something like WD-50 to make it easier? Other suggestions?

Also, once I do get it unstuck, where can I purchase an appropriate o-ring?

WD-40 or a true penetrating oil is going to have a hard time getting to those threads. I THINK I ended up using a baby impact wrench on mine - maybe you have a friend with a small impact wrench. Use a 17 mm, 6 point socket - all the fasteners on these machines are odd english/metric sizes.

By all means be careful because of potentially wrecking other components and having a wrench slip at the most inopportune time. At worst, a small trip to Albany where you would definitely want to upgrade the valve to the latest style.

That particular o-ring is either viton or silicone and once properly sized, the most convenient place I can think of is McMaster-Carr - http://www.mcmaster.com/#about-o-ring-materials/=6tgotm

I finally got the top of the valve to unscrew! So I'll soak it in a vinegar/water solution for a few hours and hopefully that'll do the trick.