Newbie - Advice on leaking fill line valve...

[Variant]

Hi everyone -- I have a fill line that's tied into my sprinkler system. There are two backflow prevention devices on the line -- the one closer to the pool is electric/solenoid and the one prior (and higher) is manual.

The manually operated anti-siphon valve is leaking when open and so I'm looking to replace.

My first thought was that I wasn't sure why this system had two anti-siphon / back flow prevention devices. Couldn't I just yank the manual one out and rely solely on the electric one? Secondly, wouldn't my sprinkler system have an anti-siphon device further upstream somewhere?

From posting elsewhere, I've learned a couple of things:

• By code, I probably really should be using a reduced pressure back flow assembly. In addition to the electric anti-siphon device?
• I'm not sure that I should have PVC above-ground. At the very least I think it's supposed to be metal on the source side and silver-painted after. Or else enclosed. Not sure that this is a code violation, just a best practice.

For what it's worth, I'm in Southern California.

Thoughts?

 

[Melt In The Sun]

The lower one is not a backflow preventer, just a solenoid valve...so you do need it. Why not just get rid of the lower one and use an automatic valve w/ backflow preventer? Can't really help with the code questions, but that's the first I've ever heard of PVC not being OK to use above ground. It should be painted though, to protect it from the sun...looks like yours is not.

 

[Variant]

That makes sense to me. Not really sure what the thinking was with this thing...

Have read through California Plumbing Code (exciting) and do see where it's referenced that you need the reduced pressure back flow device when you're dealing with the risk of pool chemicals. However, it isn't clear if this is meant solely for the case when that water supply is pressurized on both sides. In this case, the pool waterline is 18" lower than the fill line valve and obviously I don't have a pump hooked to the outlet of the fill line. Just not seeing the risk of pool water getting back into the main water supply if I lost main water pressure. Plus, I figure my sprinkler system (off of which this fill line runs) has its own back flow protection device before it hooks into the main (guess I should go look for that).

EDIT: Reading code again, the two criteria listed may BOTH need to be true in order to require a pressurized back flow preventer. Fill line must be submerged as well as wired into the pool circulation system (which would obviously be pressurized). California Plumbing Code 603.5.21 (2013). Seems to me that the only risk with only the submerged fill line is if my valve assembly and piping are below fill line level.

 

[Killer95Stang]

Has this been in use for a while? Did it work all this time? If the answer to both of those questions is true, then just buy the $15 in parts to replace it with a new one. Stop over thinking this. Manual anti-siphon valves eventually all fail and leak. Good thing is, they are cheap to replace. As long as its higher than your water level, then it is installed correctly.

 

[one_knight4u]

When we opened our water purification business years ago, the permit dept would not sign off untill we had a backflow prevention device. When asked why, we were told its to keep from pumping any water back into the water supply(read water and/or any chemical that would harm human population). Because we were dealing with high pressure (our R.O. pumps would supply over 200 psi), they required a triple stop anti back flow device, all brass and it wasnt cheap.