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Two very different things. Go to sprinklerwarehouse.com and look at the backflow devices. Sounds like your old one might have been a Pressure Vacume Breaker - PVB.

Maybe call in a pro to help you with it and show you how things work. Or if it was indeed a PVB, buy one and put it in.

It is a Pressure Vacuum Breaker that is supposed to be in a location where the backflow preventer is higher than the highest head. Very likely the original part was a chump-change imitation that can't function under continuous pressure.

Read the instruction sheet that comes with the 765 ~ you need to know it will suffer damage if the water in it should freeze

Shutoff valves won't keep it from freezing. You need to drain it, and the shutoff valves, or it can break from freezing.

Quoted from "joshknight"

My backflow valve seems to be constantly trickling water out of it as long as a water supply is on. This use to happen only after the sprinklers would shut off but now it is doing it non stop. Is this easily fixed by getting a new one or is it something more involved, IE getting a new electronics panel or...?

It all depends on which type of device you have, to me it sounds like a Reduced Pressure Zone Assembly (RPZ) or a Pressure Vacuum Breaker (PVB). Either way, this has nothing to do with electronics. If its an RPZ, which I'm assuming it is, there is probably some dirt/debris stuck in the first check. An RPZ will have a first check, a second check, and a relief valve port. Does it continue to drip when the system is running water? If if doesnt drip while running, it is most likely a first check problem. Both the RPZ and PVB can be repaired or you can replace the whole valve as well. A few things you will want to do is get the brand, model number, and size off of the I.D. tag on the backflow device.



The reason it used to drip when the sprinklers shut down is when they close it is a quick solenoid valve slamming shut causing a shock wave to travel up the system and the backflow will dump off the extra pressure to equalize the system pressure. A lot of times you can solve this problem with a hammer arrestor or expansion tank. after the backflow preventer. I hope this helps you out, any more questions, please feel free to ask.



-Josh

backflowpreventer.com