# Hunter PGV oscillating with dripline



## anticowboyism (Aug 3, 2020)

Having a hard time wrapping my head around what happening with these valves. I could use some insight. I have 2 zones of low flow irrigation on Hunter PGV-101 valves. Mainline pressure is at 100psi. I've installed the Hunter Accu-set on each valve to bring them down to a more appropriate level.

Zone 1 is a series of spray to drip retrofits, which provides a 30psi regulation. My 100psi is obviously too high for them to handle, hence the Accu-set. When I try to bring the pressure down with the Accu-set, the valve vibrates excessively. I can't get it stable at the proper pressure or flow.

Zone 2 is 2 soaker hoses, with inline MHT pressure reducers. 100 psi is again too much for these, so I try to use the Accu-set to bring the pressure down. Again the valve vibrates excessively at what should be a proper pressure (between 20-30psi).

Hunter says that these 1" valves can use the Accu-set, and the literature states flows as low as 0.2gpm are achievable. But I've also heard that the 1" valves cannot use the Accu-set because there is not enough flow thru the diaphragm to the solenoid seat to make it function properly. Any thoughts to a workable solution here would be appreciated!


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## g-man (Jun 15, 2017)

I think the min gpm is 5 for those accu-set.

What about using a prv on the main line?


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## RVAGuy (Jul 27, 2020)

These valves require a differential pressure of 15 PSI AND a minimum flow of 5 GPM. You hit the differential pressure (unless you aren't flowing enough and as a result both sides of the valve do not have a 15 PSI minimum). My understanding is you may not have the flow required.

You may have to add heads or increase your Accu Sync to a higher PSI. If you increase your downstream PSI, you will increase the flow, just keep in mind you still need the 15 PSI differential. I would buy one of their adjustable Accu Syncs (AS-ADJ) and see if you can tune it in (with a higher pressure to increase above minimum flow, but a pressure low enough to give the 15 PSI differential).


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## anticowboyism (Aug 3, 2020)

I installed a prv on the mainline yesterday, and removed the Accu-set. The valves are now working fine. I have the PRV at 40psi right now, which is still a bit high for the drip and soaker zones. Those have little plastic mht inline pressure regulators which bring it down to 25psi. Seems good for now. I would love to have something more robust than these mht regulators to bring these down to 15psi permanently.

Thanks for the help.


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