On our last outing in June, I noticed that in turning the A/C on via the control knob on the ceiling, I went through both Low Fan positions without the unit making a sound. When I hit High Fan, the blower started and when passing through Low Cool, the blower stopped, but I could hear the compressor running. I finally landed in the High Cool position and we had a good camping trip in cool comfort.
I decided to work on the unit this weekend ... hoping to determine whether it was a broken wire or a burned out blower motor winding. I killed power to the unit and pulled out the control panel so I could bring it inside to troubleshoot the switch. Sure enough there was no continuity between the line in and the out pin to low fan speed. I unplugged all 5 wires on the switch and tested continuity in all the various knob positions. I decided to open the switch to see if there were any burned contacts within. Once opened, I immediately saw nothing burned, just everything covered in a very thin grease, I broke out the alcohol and cleaned everything to remove the oily residue. I put a tiny dab of silicone lubricant on the rotary part and the bakelite axle and re assembled the switch. I tested continuity before I crimped the cover back into position...all positions showing continuity at the appropriate position. I reassembled the control panel into the A/C unit, set the circuit breaker and went through all the positions. I now had Low Fan and Low Cool, as well as High Fan and High Cool.
Conclusion: The Chinese made control switch should never have been lubricated with low temp grease that would liquify in the 90 degree + temperatures at the ceiling of a closed up camper in this SE Louisiana heat.
I hope this may help a fellow forum reader with a similar problem. Had I just replaced the switch, the problem would have likely recurred over time. ............... Swampy
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