I have a 1983 Manufacture GE Weathertron Elite...outdoor heat pump, crawlspace coils, etc. It started acting up the other day. Having been away a day, I don't know if there was a storm involved, or it's just the annual glitch.
During cooling cycle, initially it is fine. But after a while, the solenoid begins clicking on and off, causing the reversing valve to kick in repeatedly. If turned off, and allowed to sit, and then restarted, will cool normally, and quietly for the first 5-10 minutes (pipe going into house is very cold), then eventually the solenoid will click a tiny bit, slightly, just a blip, then get worse over the next few minutes. I put a voltmeter to the power leads to the solenoid and things are steady at 26.1v...until there's a click, then it's a dip to 24, or 19, or 9 for the loud ones where it almost completely reverses, then when fully reverses, it's zero. But power returns shortly after sometimes...sometimes not. The 240v defrost timer is rotating, and other than minor pitting on the contact pair I could see (one set was closed the other open), did not seem to look bad.
What would cause this kind of behavior? If it is the solenoid coil, how to do I get the solenoid off the pin there? (open frame coil, Alco AMF-24v 12W) The only thing I see is what looks like a silver cap on the end preventing it from coming off to the rear of the valve, but sure doesn't seen to screw on or off?
Could the interior thermostat, or one of the 2 thermostats there inside the heat pump cause this intermittent powering of the solenoid?
A) one on thin pipe riser to outside coils
B) one on thick pipe near expansion area (?) compressor
Something else? This is attached to a load controller. They don't go bad do they? Wouldn't cause this behavior I wouldn't think. Low refrigerant would not do this would it? I know this is a lot to throw out in a single post, but I'm just trying to work it out.
Thanks for any suggestions. I'm kind of in a bind right now, money wise. A defrost control is pricey even at DIY price, about $180 for the Trane CNT-2236 which replaces this older 240 v clock type. I can see it spinning though...
I would think solenoid is faulty given the behavior, except even if it was going open, the voltage should still be 26v at the supply side where I am measuring it?
Thanks for any advice.