Random stuck Hunter SRV valves.
I have a 6 zone Hunter system with SRV valves. Over the last month I've had several of the valves stick in the on position. I thought the problem was isolated to failing valves because the plastic rings were cracked. This has not fixed the problem though and different valves are sticking at different times. I then thought possibly it was the controller but after testing the connections at both the controller and valve end I was able to verify that the controller wasn't sending any signals to the valves. I even went as far as to disconnect the valve wiring and the valve stayed stuff open. I tried switching out the solenoids between two different valves and it didn't help. The only common thread is that the replacement diaphrams didn't come with new plastic rings that supported the diaphrams like the original valves had in them, some of the original support rings were broken. Any advise for trouble shooting? I'm tired of random valves common on at random times. Lastly i have gone through all the valves that I opened and made sure to clean everything.