Coleman ac problem

Controls at wall thermostat, or manual at ceiling?

Sounds to me that the compressor start capacitor is the first thing I would check. You will need to get on the top of your camper and remove the outer cover. The capacitor is the part that stores up enough energy to kick start the compressor when it starts. Sometimes a capacitor will swell if bad, but not always. Mark your wiring before removal and have someone test the capacitor to see if it needs replaced. I will be here should you have any questions. If helpful please rate this solution, Thanks Sea Breeze

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comparison_good_and_bad_round_capacitors

You need to get a reading on the current draw of the compressor. Use a clamp on ampmeter to do this. Compare your reading with the data plate on the compressor. Your compressor may be getting ready to go out. You can also check the capacitor. If may be getting weak and need replacing. Another idea may be to install a hard start capacitor if the compressor is OK.

in the main electrical fuse box in the camper

Replace the start capacitor for the fan and compressor. Check all the wires to the capacitor.

How long has it been there, without experiencing any problems? This just start recently? Have you cleaned intake air filters at ceiling? Fan keeps running?

I am afraid your compressor has gone to the hills. Replace

no cold air; clicks on then off.

I had a problem with my coleman mach 3 AC, we were at an RV park up at lake shasta CA and the fan would stay on but the compressor would come on for a few seconds and then trip off. It was the motor overload relay on the compressor that was tripping. the RV park was old and apparently the wiring to the panelboard at the RV park was too small, when you are drawing a lot of current there was too much voltage drop across their line, to make up for this the motor tries to draw more current and heats up the motor overload and it trips off. I solved this problem by buying an autoformer from Camping World, it senses a voltage drop and automatically boosts the voltage.

I am now having a seperate problem, the compressor is either locked up or has too much back pressure and trips off the service breaker when trying to start. The only solution I can see with my current problem is to replace the entire unit.

I would check the thermostat based on what you said it could be out of calibration