Anti-Siphon valve leaking

When I test both exterior faucets for pressure, one of them had water coming out underneath the Anti-Siphon valve cover. Any thoughts on this? First time I have had one do this.



Hi Charles,

I have seen them do that, the problem is that the washer/seal has failed or is crudded up, rebuild kits are available for most of them very cheaply $5 - $10 write it up as in need of repair



Thanks Gerry…I appreciate it. It does not leak when nothing is connected to it, but if I put the pressure gauage on and have a little back pressure it leaks.

Yep that’s what they do when the seal has failed, the back pressure valve that is supposed to seal off the supply leaks and the pressure is directed to the outside of the valve under the cap.

Actually replacing the valve is very simple, once the plastic cap has been taken off the valve stem can be undone and the main seal replaced.



I will have to disagree as nationally certified ICC residentail plumbing code inspector with Gary Beaumont’s comments regarding ‘replacing’ and ‘rebuilding’ atmospheric type vacuum breakers.

While such ‘vacuum breakers’ might be able to be rebuilt, they will certainly lose their listing and labeling by their manufacturers if so done…and therefore become an illegal appliance if continued in use unless recertified by the 3rd party listing and labeling agency.

That said, the ONLY correct action is this case is to replace the entire hose bibb completely so that the new one is listed and labeled for its use.

‘Rebuilding’ is not code compliant under the IRC plumbing code provisions even in Florida unless Gary Beaumont can show otherwise.

What I see is a code violation and the entire hosebibb assembly needs to be replaced not “repaired”…

Here is the drawing and the listed repair kit. pn RK-17

Hi to all,

I can find nothing in chapter 29 of IRC 2006 that suggests that repair of backflow preventers is not permitted, and all the manufacturers that I have looked at this morning have repair kits available.

I will be very interested to see the code that you mention



I don’t see how the repair of any “listed” component with properly listed repair parts by qualified persons would invalidate the listing of a device-----otherwise how could you fix anything in the electrical, hvac or plumbing world?

Mr. ICC certified plumbing code inspector; please get a life. There’s more to life than being uptight about everything. Try a beer perhaps. Feed some needy people. Do something other than voiding the world of common sense solutions to simple problems. If we were all tightly wound like that cars and gasoline would be illegal because they can and do kill. Seriously. How does somebody like yourself even prepare a meal??? You could cut or burn yourself! Oh my!


Maybe you non-members shouldn’t worry about 6 year old threads.

Gerry died several years back. I assume you were referring to his post. Hopefully not. :roll: