Return to the Irrigation Forum | Post a Follow-Up

Anti-siphon valve questions

Posted by chocotaco CA (My Page) on
Mon, Dec 9, 13 at 15:33


When I moved into my house, all of the irrigation valves were seized up and the lawn was already dead (it was bank-owned before I bought it).

I decided to replace all the valves (this is after two years of dead lawn... heh) and I noticed that even though they are anti-siphon valves, they are not above all the sprinlker valves - there are areas of my yard that are higher than the valves. So clearly whoever did this originally didn't really understand what they were doing.

So my options now are to either

1) Have anti-siphon valves that are a few feet above the ground
2) Isolate the areas that are higher than the valves and instead run an underground line to those areas and install an in-place anti-siphon valve 6" above that zone - is this allowed/possible? I guess the underground line before the AVB might defeat the purpose but I'm not sure.
3) Install some other backflow prevention device - from what I've read about CA regulation, this would have to be a RPZ assembly which is expensive and requires professional install.

So if option #1 is to be it, how should I go about hiding the valves? Are there enclosures that are designed for sprinkler valves which are several feet (probably 3') high? Or do I have to build something out of retaining wall blocks or cement board or something?

Another thing I read in the course of my research is that the inlet pipe to the sprinkler valve needs to be metal until it gets 18" underground. Is this a concern? It is not this way currently. I have 8 zones so it's going to be a lot of work. It seems like this would also mean that the manifold must be metal, which doesn't make a whole lot of sense. I included the source link for this, if anyone can clarify that would be great!


Here is a link that might be useful: Source for metal inlet pipe requirement

Follow-Up Postings:

RE: Anti-siphon valve questions

The reason the line is metal to 18" underground is because the pipe will always be full of water under pressure and water freezes to 18" underground and it will burst a PVC pipe. Usually the copper pipe is connected to the copper pipe from the house and immediately connects to the ASV so it doesn't freeze. If you have a system connected to the water source pipe before the house in the yard put a gate valve immediately after the connection point and turn that valve off during the freezing winter weather so there is no water after the valve up to the ASV. Also, blow out the water in the system itself for the winter. If you don't have freezing weather then disregard the above.
For the ASV locations, you can have several ASV along the line that decrease the heights of each one if you have steep sloping areas. If you have tall ASV systems, you can hide with hedges or other vegetation or behind other hardscape. JMHO Aloha

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Irrigation Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here