Question about Dometic Rooftop RV Air Conditioner

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Have Dometic 600315.331 Have checked both caps, relay (PTCR), compressor windings (open & short)- All check OK. I wonder if we have low freon? Suggestions??? Thanks

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  • s_heyer Sep 25, 2009

    Thanks Terrencio. When switched on fan runs, all modes, but compressor does not appear to try to start at all- no hum for even a second. 2)I have continuity between all, r/c, s/c, r/s compressor windings but no reading to ground. I believe it is Okay. 3)I checked the caps, both start and run with ohm meter, both deflect and return. I have not put an amprobe on yet because I don't think the compressor is trying to start. By the way I also checked the PTCR which has continuity and the overload. I didn't see any low pressure switch either in the schematic or on the physical unit. Where do I look next? Thanks.

  • s_heyer Sep 25, 2009

    Could you send me the link to the service manual? Thanks

  • terrencio
    terrencio May 11, 2010

    I found the manual online, the wiring diagram does not show any low pressure switches that would shut it down due to low refrigerant. So I have to ask a few questions. 1 what does the unit do when you switch it on? Hum? fan only? or nothing? 2. when you say you have checked the compressor windings, what are the ohm readings, r-c,s-c, and r-s, and is there any ohm reading from any winding pin to ground, not continuity, but ohms check? 3. When you say you have checked the caps, is this an ohm meter deflection test, or capacitance test, if capacitance what are the readings as compared to the capacitor ratings? I am more interested in the run cap than the start cap at this point. 4. If the compressor hums but does not start, what is the amperage draw? with the above info. I will be better able to assist.



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Dometic has had a bad run of pc cards the've been changing. Contact a dometic dealer and make an issue over the curcuit board and once hey get it lit, They can tell more about the refrigerant charge. Good Luck, Ned

Posted on Sep 25, 2009


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