SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

You seem to be intent on fixing something that isn't broken. Can you elaborate on just why? The spilled water is not a health hazard, and you probably haven't yet tried lowering the zone pressures with the flow controls on the zone valves, which would reduce any spilling.

Thanks Wet Boots! Which inline sprinkler valve do you recommend?

I heard that some breakers occasionally eject some water, do you know a good spill-resistant pressure vacuum breaker?

They do not. That's where the hundreds come in. Install a Pressure Vacuum Breaker, along with underground valves, and no water exits anything but the sprinkler heads.

Do inline sprinkler valves have the same problem?

How many hundreds of dollars are you willing to spend to make this go away?

strange thing happened. After I replaced the two spring-loaded sprinkler heads with regular heads in zone 3, water not only gushes out from the anti-siphon cap of the 3rd valve, but also from the 5th valve again. Any ideas?

You might complete the experiment by switching back one head, and see what results. This isn't strictly about the spring-loading, but about whether the heads can gush water when they are not completely popped up. (sometimes called "flow-by")

You are absolutely right! After I replaced the two spring-loaded sprinkler heads with regular heads in zone 5, no water gushes out from the anti-siphon cap of the fifth valve any more. Now water gushes out from the anti-siphon cap of the 3rd valve because there are two spring-loaded sprinkler heads in zone 3. I will replace them with regular heads tomorrow.

There are no spring-loaded sprinkler heads in zone 1 and 2. There are spring-loaded sprinkler heads in zone 4. But they are located downhill. So I don't expect the same problem in that zone.

Thank you very much for your help!

Not from the information you provided. In any event, this 'flow-back' has been known about for decades, and the anti-syphon valves are still code-approved.

Thank you very much your inputs. The fifth zone do have two spring-loaded sprinkler heads. But zone 1-4 also have spring-loaded sprinkler heads. Any idea why water gushes out only from the anti-siphon cap of the fifth valve?