Well, I just got out of the rain finally defeated. My moms house had no a/c, so I roll my happy ass over there and find a capacitor failed from last year. So I replace it, as well as the start cap for the compressor, and hey, why not the original contactor to, wash the coils (plugged of course) and also found the installers of my moms furnace forgot to reinstall the rc rh jumper, fine. Started up the system, sh sc head and suction all looking pretty good.
She has a 20 year old trane heat pump, with defrost board.
So, I was smoking (yeah oh well) and I noticed that the smoke got sucked into the top of the motor.. then I double and triple checked myself and turned off power and checked rotation, CCW LE, but it was running clockwise. This is a standard 240, single phase system. So, I started simple, I checked all connections (good) and wiring (good) I replaced the run cap for the condenser fan motor with the old one, and checked all the wiring to the motor. All of the spades are insulated so I really couldn't check power as much as I wanted to in the pouring rain, but I have a feeling that a winding has shorted into another, or has failed, causing reverse rotation. I have never checked voltage at a capacitor, but attempted to, and found 120v on one side (common) and then 240v on the load side of the run cap, this is just a standard 7.5 mfd dual cap, I did not run the system before I got there because the system needs charged every year, so I didn't try and start it (yes I know)
But my question is, has anyone ever tried to check voltage at a cap? My voltages were from each spade to ground, 120 on common makes sense, but 240 does not on the other side, contractor has no voltage drop, and the wires for the condenser fan motor are on separate poles. And does my diagnosis sound correct? I've only seen one other fan motor running backwards, but it was on a carrier rtu with a motor master.. this is blowing my mind... sorry for the long text
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