I have an old rental mobile and the heat pump is operating normally, except the outdoor unit fan is running all the time (unless the breaker is off), and it runs very slowly. The run capacitor measures 28uf versus parts websites showing 35uf.

I might believe that might cause the slow problem, but not the "all the time" problem. The schematic shows a one speed fan, so I don't think it's confused about what it should do. Also, the schematic shows the "run" capacitor wired as a start capacitor for the compressor. The "start" capacitor shows being the start cap for the fan.

enter image description hereIt heats fine, although it ices up quickly due to the lack of air flow. I didn't have a meter when I removed the capacitors, so I can probe a little more tomorrow.

I did replace the wiring harnesses in the indoor unit a few weeks ago as they had developed an intermittant and melted everything. It's a 3500A912 unit with a 5871 adapter. If I need a new heat pump, I'll scrap the mobile. Unfortunately, I just spent a couple $K doing ceilings and carpet.


The motor to shorted to the case. It will need to be replaced.

  • You're exactly right. I discovered the case was shorted to a winding before I saw your response. Thanks! – user263463 Jan 12 '18 at 19:45
  • Finally got the new fan motor and everything looks proper now. – user263463 Jan 27 '18 at 14:14
  • Cool. Happy Cooling. P – Paul Logan Jan 28 '18 at 21:40

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