Question
I have a Hunter ICC and when the system is placed in service, either in auto or manual, the station turns on. Then in a short time I get an error code "P Err" on the panel and the system shuts down. What does this error code mean? There is a wire terminated on the P/MV terminal. Do I have a bad main valve solinoid?

Answer
Hey Larry, you are correct in that there is a problem with either the wire that runs to your master valve, or the solenoid on the master valve. First disconnect the solenoid on the master valve by taking off the wires. Now turn the controller on and see if you still get a P Err message. If you are still getting the message, then the problem is in the wires. If you no longer get a message, then the problem is the solenoid, and you need to replace it. Good luck and have a great day.