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SC_camper's avatar
SC_camper
Explorer
Jun 19, 2014

Coleman mach 3 ac freezing up

We are having a freeze up problem with the ducted Coleman mach 3 ac unit. The evaporator is clean and the filter is new. We run it on high cold and turn the thermostat down from max cold. This past weekend was in the mid 80s and humid but still had a freeze up over night, low 70s. My question is about the copper temp sensor wire. It is in front of the evaporator but not touching it. Should it be touching? I dont hear the compressor cycling. Should I turn the thermostat warmer to make it cycle? It blows good cold air until it freezes up. What else can I look at before taking it to the shop?
  • SC_camper's avatar
    SC_camper
    Explorer
    Jun 22, 2014
    dougrainer wrote:
    SC camper wrote:
    Thanks for all the input and help. I need to check into the thermostat next. This is likely a dumb question and I probably know the answer but; can I plug into my outside home power outlet(15 amp) long enough to check for tstat operation? I dont have access to 30amp until we go camping again. Is there a way to check the tstat operation with an dvom without shore power plugged in? I guess that would be ok for checking the temp switch but dont know about tstat.


    Yes, NO power you still turn it max and minimum. You should hear the contac point click open and closed. Doug


    Thanks for the help Doug. Could you clarify, "Yes,NO..."? Yes, (I can check it with out being plugged in), NO power you still turn it max and minimum and hear the contact open and close. I just dont want to try it without power and condemn a part because I didnt check it properly.

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