Question about Dometic Rooftop RV Air Conditioner

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Have Duo Therm roof mount A/C. Fan runs but when compressor tries to come on it just has a hum sound for about 10 seconds then after a short period of time it tries again but will not kick on

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  • jwmdm Feb 28, 2009

    There was a "Squirelized" wire. 10 minutes to fix


  • craig_lowell Apr 22, 2009

    I have a duo therm roof mounted system on my RV. A couple of days ago it quit working altogether. I replaced the thermostat and relay controller box but that did not wrok. When I go to turn the system on, all I get is a clicking noise coming from the relay controller box. The compressor will not even make a noise. Also, the fan will not come on if I try to turn it on from the thermostat box. Could it be that the starter capacitor for the motor and the capacitor for the compressor is bad? Or is the compressor frozen up. And if it is, would it be better for me to buy a new ac system.

    Thanks for your help,




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  • 144 Answers

It sounds like the compressor is locked up. You can try a start boost or hard start kit but once this starts the compressor is on it's way out.

Posted on Feb 26, 2009


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