What is the best way to check to see if the solenoid is opening?
I have a 5 zone system with the irritol 2400T valves. One of the zones will not come on. I checked for voltage to the valve and it was fine so I replaced the diaphram & the solenoid but that didn't help. If I open the bleeder valve the zone comes on. I took the valve back apart and inspected each component and there doesn't seem to be any noticable faults. Any thoughts?