Question about Intertherm P3RC-042K Air Conditioner

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Outside fan motor won't come on. I can depress the contactor and it will run but will not run via the thermostat. Perhaps the control board is bad. Where can I find schematic?

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Does the indoor fan come on? At the thermostat take the fan from auto to run. If the indoor fan doesn't come on then the problem could be the transformer. It could also be the coil in the contactor. Both of which are a lot cheaper than a control board. It could also be your thermostat. With the thermostat calling for air check for 24vac on the coil of the contactor. If you have it then the contactor coil is probably bad. If you don't have it I would suspect the transformer or and overload or pressure switch. Check for 24 vac at the transformer. If you have 24 vac there go to the thermostat and place a jumper for R to Y and see if it comes on then. If it does replace the thermostat. Let me know if this helps or if you have more questions.

Posted on May 05, 2010


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