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Klueck's avatar
Klueck
Explorer
Jan 10, 2014

Duo Therm AC and heat pump not working

We have a Dometic DuoTherm Ac with heat pump that's not heating or cooling.

For over a year,there was a crackling noise when the compressor quit running, but it cooled and heated fine.

Now, we've notice neither the heat pump or the cooling is working. Our front Ac unit runs fine.

The fan works fine, but when I have the AC on automatic, the fan just keeps running, but it's not cooling.

Any ideas what this may be??

2 Replies

  • dsomervl's avatar
    dsomervl
    Explorer
    Jan 11, 2014
    First, go to the front A/C, and listen to it when it starts up. You should hear the fan blower start(air starts moving), and then about 2-3 seconds later, you hear a low rumble with a vibration that you can feel with your hand. This is the normal startup either for A/C or heat pump.

    Now, you should do the same on the unit that's not working. You probably won't hear the low rumble/vibration. That's the compressor not starting up.

    You've probably got a bad start capacitor, or bad compressor.

    Now you hope that it's only a bad capacitor.

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