Leaking vacuum breaker on Moen hot/cold faucet HC400510

[tj53152]

Good morning,

Hoping someone can help me get to the bottom of this issue. We have a Moen hot/cold anti siphon faucet installed in our barn wash rack and it leaks at the vacuum breaker. It has not always leaked, but the more I look at the installation, I'm questioning why not. It was installed vertically vs. horizontally because the other side of the 2" wall is a horse stall, and the hose connection goes up overhead (see attached photo). I've replaced the vacuum breaker, but it did not stop the leak. The leak occurs when the faucet is turned off and the hose valve is opened to relieve the pressure on the hose. It appears that the water from the vertical run of hose is draining back through the vacuum breaker, which would sort of make sense as it's the only path for the water to take and the vacuum breaker is lower than the hose. However, I can't figure out why it hasn't always leaked and how to fix it now that it does. Any suggestions would be greatly appreciated.

Thanks,

Terry

 

[Reach4]

It looks to me as if you are missing the cap on the vacuum breaker. That may not be important to the function.

I suspect Moen would say that you need a new vacuum breaker repair kit. However you might get by with just cleaning the old one, or replacing the o-ring with a generic o-ring of the proper size.

I am thinking the white thing screws in, although I have never seen a Moen vacuum breaker. So I would try unscrewing it.

Moen Vacuum Breaker Kit for Sillcock 140900 appears to be the right part. I am not a plumber or other pro.

http://www.moen.com/shared/docs/exploded-parts-views/hc400506pt.pdf

http://pro.moen.com/moen/vacuum-breaker-kit/_/R-TPORTAL-ALL:140900
List price $9.70

 

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[Terry]

The leak occurs when the faucet is turned off and the hose valve is opened to relieve the pressure on the hose. It appears that the water from the vertical run of hose is draining back through the vacuum breaker, which would sort of make sense as it's the only path for the water to take and the vacuum breaker is lower than the hose.

I have no idea why it didn't leak before. It should have leaked, as it only seals under pressure. It's meant to "breath" Maybe there was enough head pressure to make it shut off.

 

[tj53152]

Hey guys,

Given the barn has never gotten below freezing (maybe 34 degrees at worst), I decided to put a washer and o-ring on the back side of the vacuum break to close it at all times. Now, we can disconnect the hose if we thought it could ever get below freezing, but we'll likely never there. So the leak is solved.

Thanks for the replies.

Terry