Question
Hello,

I have a 2 year old Hunter system consisting of a Hunter Pro C controller, a Hunter-22 pump start relay (PSR), driving a Berkeley (AO Smith) 2.5 HP 220v pump. System was wotking fine until the other day when, at start up, I got a  P ERR (pump error) message on the contoller screen.  I examined all the connections and found no trouble. I carried the pump into the basement shop and powered it directly from the panel breaker (bypassing the PSR) and it ran fine. I cleaned out the pump section (it wasn't dirty), reinstalled it and the system operated again for a few days. Now I'm getting the pump error message again or the 220 breaker trips. I'm begining to suspect an intermittent operation of either the controller's 24V pump circuit or the PSR. Can you help me diagnose the issue?

Thanks

Peter

Answer
Sorry for my delay of answering.
My guess is your PSR relay isn't making contact on one of the points and is causing the breaker to trip. Simply put, your trying to run a 220 volt pump on 110 volts. The intermittent operation indicates this is the problem.
The relay contacts are subject to burns just by the nature of what they do. Compounding the problem can be insects. An ant in the relay box between the contacts will burn into an insulation. I see 5 - 10 of these a year. If you see any insects in or on the relay box, you'll need to "evict" them.
Good luck.

Matt