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Serious problem with anti-siphon valves

Lis77 | Posted in General Questions on

We have anti-siphon valves on our exterior spigots, as code requires. I understand why these are necessary and that they are important. But they spray water out all over the house siding every time the water pressure changes i.e., if the washing machine is running or someone inside uses a faucet. We are beginning to have problems at the area of the house that is constantly wet. I’m seeing carpenter ants now. Isn’t there some better way to prevent siphoning from the garden hose without this issue of water spraying out all over the house siding continually? It seems like there should be a better way but I’ve searched for alternatives to these devices and can’t find anything.

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  1. charlie_sullivan | | #1

    It shouldn't be doing that. I would think in terms of taking care of your water pressure problems:

    1. Install an expansion tank or water hammer arrestor to reduce the spikes in pressure, near the washing machine or near the spigot or both.

    2. Measure your water pressure. If it is high, get a pressure regulator installed where the water main comes in. 80 psi is usually considered the maximum safe pressure, and may be a code requirement. You might want it a little lower to be safer.

    I would take some temporary measures to protect the siding until you get it fixed ... Either shut off the supply to those spigots, or make some kind of deflector from aluminum flashing?

    And follow those ants to find their nest. Leave them some boric acid based bait. And consider more drastic measures against them.

  2. JC72 | | #2

    Sounds like a failing water pressure reducing valve . It is installed one the house main. The Plumber who replaced our said they last about 15 yrs.

  3. Bill_NC | | #3

    I've had good luck with Woodford anti-siphon valves. Home Depot sells them. Different models for freezing conditions. If you call Woodford's tech support line they can probably help you solve this problem.

  4. Lis77 | | #4

    Thanks very much for your replies. I am surprised to hear that the valve should not be doing this.My experience is these valves always do this and when I've spoken to others about it, they have also said theirs do the same. All the plumbing in our house was redone about 10 years ago and these valves have done this from the beginning. The Woodford valve looks promising but I would have to open up the wall and replace the whole existing spigot, wouldn't I?

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