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

There are valves that prevent backflow in the valves, called anti-siphon valves. The other type of valves are just valves that do not have any backflow prevention device, so you then need a backflow device connected to your mainline BEFORE your manifold of valves. If you install anti-siphon valves, there is no need for a backflow device.

I typicallly prefer the "regular" valves, such as the Rainbird 100-DV

Thanks!

It depends where you are located. Some local codes prohibit the use of anti siphon valves, like around here!

Thanks
Ray
Rays Above and Beyond Automatic Lawn Sprinklers

An anti-siphon control valve is NOT an aceptable substitute for a backflow preventing device. All control valves will leak eventually. Not if...when. The lowest protection device...a double check preventer is about $80.00. Well worth the peace of mind. IF you use no device at all, even with antisiphon valves, you risk allowing effluent into your household water supply. The consequences of that can be dire.....not to mention expensive.

I definatly believe in installing inline valves and a seperate backflow device...for reasons that were hit on the dot in previous posts.....eventually valves fail, tear inside, or breakdown, and if the backflow you are relaying on in the valve fails then you will have a huge problem with series consequences. I would install inline valves (Irritrol 2400T Preferred) and a Febco or Watts Pressure Vacuum Breaker or Double Check! []

I've got anti-siphon valves and an actual backflow preventer. Originally, I was going to hook up to the main city water, but decided to go with a well instead. Will I still need a backflow preventer and will this cause significant pressure drop on the pump i plan to use for the well? Thanks for any help. Edit: Also, is it a fair bet that I be able to use the anti-siphon valves along with the Backflow preventer for the well?

yes you need a bak flow preventer in this situation and I see no problem with using a back flow preventer with asv's. What type of back flow preventer are you intending to use? Are you having a well dug for you?

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by drpete3</i>
<br />yes you need a bak flow preventer in this situation and I see no problem with using a back flow preventer with asv's. What type of back flow preventer are you intending to use? Are you having a well dug for you?
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">

I'm not even sure what type of backflow preventer it is right now. The guy at Lowe's just basically told me that would be what i needed to run with my Rainbird setup. It's made of pretty tough pvc and rated to 200 psi. Looks to be a slip on piece that installs like 12" higher than your sprinklers in the yard. Any pics on this site that i could compare this to? Thanks again for the help.