Roof duotherm ac not working

Do you have the digital thermostat? You can tell the thermostat you have no furnace. You should be able to disconnect power at the furnace, but the 12v power for the circuit board is provided by the furnace circuit on some systems so make sure you disconnect the wire going to the furnace and leave the wire feeding the circuit board.

power is ac so there is no polarity problems, one power to circut breaker, one to the other location. Only one to breaker

Trace the wires from the compressor back to where they come from. They should be coming from a contactor or from the circuit board. It's possible the relay is built into the circuit board (it will look like a little black box on the board. Let me know what you find.

Hi, do you know what these wires were for? You can bypass the board, but if the wires are for lets say the blower motor and you bypass and put them to direct hot legs, you will run all the time, or what ever shorted the block in the first place must have a short. Its probably in the wires at this block and if you apply it to 120 volts it may fry again. I would follow these wires back to see what they run first. Yes, it can be done.
Shastalaker7

I'm not sure what the problem may be but you could try calling All Seasons RV Appliance Parts & Service. There number is 1-800-344-0673 they have helped me in the past. That and there tech calls are free so it wouldn't hurt to give them a call.

The main Pcb as well as the defrost thermistor are in the circuit as well.
The thermister is attached to the evaporator with wire ties and connects to the roof of the freezer behind the fan assy.

I have seen the thermister connector pull out of the connector at the top of the freezer beacuse the wires were to tight. Remove some of the wire ties and reinstall the connector.

call duotherm, they have a series of bad pc boards

I had to get on the roof of mine, remove the cover and manually spin the fan. Add a little oil to the shaft where it goes thru the bearing. All of this is done on the roof side. Mine required this procedure every spring. Duotherm realizes they had a problem and have since corrected it but they don't deal with all of their customers that had the original problem.

try make new traces to circuit board by soldering it will be hard depending on how small the trace wires are

You must have too many things running on that circuit. Check your connection to the power box.Loose connection on the receptacle can cause the breaker to trip or too many things running on the same circuit. If the breaker is old it might need to be replaced.

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