Sprinkler Anti Siphon valve is leaking from cap

[JoeyDYI80]

Tonight after I manually turned on one of my sprinkler zones for few minutes and after it was done I noticed that water was continuously leaking from the underneath the cap of the anti siphon valve. I thought it would stop after a few minutes, but it did not. When I tried to turn on the sprinkler zone again the water would stop, but after closing it again it would leak again. So I just went ahead and shut off the valve for the whole sprinkler system until I was able to troubleshoot.

So in my situation do I need to replace the whole anti siphon valve unit or can I just fix the cap part. I am attaching a pic with the part circled in red to indicate where the leak is coming from. Any help would be appreciated.

 

[Fitter30]

There should be a rebuild kit for it. Just google model and brand for the the parts.

 

[Sponsor]

 

[wwhitney]

The anti-siphon is downstream of the valve, so I believe either

(a) the valve isn't fully closing and is letting some water past or
(b) the zone has outlets at a higher elevation that your anti-siphon unit (which I believe it shouldn't) and you just haven't waited long enough for it to empty the zone.

Cheers, Wayne

 

[WorthFlorida]

A leaky valve would not cause the anti siphon to open. wwhitney (b) is more likely the cause.

 

[Reach4]

With a regular spigot with anti-siphon, you can clean debris out under the cap, and often need no new parts. Is it similar with a valve like Joey's?

 

[Paul DT]

Same issue - Sprinkler anti siphon lid on my Champion brass irrigation valve leaks (heavily) when this irrigation Zone is turned ON & none of my sprinklers pop out and they don't work in this zone....

It was working perfectly until this. The only thing I have recently done (not sure if relevant): Could the fact that I opened a sprinkler head (while system was working) last week and water squirted out and I turned the system off to fix it created the issue .

 

[WorthFlorida]

I answered this on your other post.
https://terrylove.com/forums/index....vily-when-turned-on-zone-does-not-work.95371/