Originally Posted by swallax
The front compressor keeps shutting off. Replaced the run capacitor but still having the same issue. Runs fine after dark but not during daylight hours. Could it be the bimetalic overload switch going bad? How do I test that and if it is to be replaced I can't find which wattage switch to use as a replacement. Any suggestions on this issue would be appreciated.
1. Disconnect power to that u it at the breaker panel, or just power down all the AC for the coach.
2. Climb up on the roof with a 1/4” and 5/16” nut drivers, #10 Phillips, #10 slotted screw driver, and a water hose with a sprayer on the end.
3. Remove the top shroud of the unit.
4. Using the water hose, carefully wash the now exposed condenser coil with pressurized water from the inside out. Watch the water for dirt and crud that will wash out of the condenser.
5. Be careful that you don’t flood water back toward the enclosed evaporator area.
6. If you feel you really need it, you can buy a coil cleaner at one of the big box hardware stores. But do t use anything that’s not intended for cleaning HVAC. Coils. Anything too aggressive will decrease the thermal transfer bond between the actual condenser “tubes” and the heat rejecting fins.
7. Once cleaned, climb back down off the roof and test the units operation.
8. Something else to check while your cleaning the condenser - make sure the fan turns freely. The bearings are usually “ lubed for life” but they aren’t. You can lube them, either by letting the fan run for 10-15 minutes, turning off, then applying light weight machine oil to both shafts as they exit the motor (requires opening up the evaporator enclosure) and applying oil right where the shaft enters the motor. The heated bearing will “suck” the oil up into the bearing. More a temporary solution than permanent.
Alternative is to take the motor out, disassemble by taking the 4 stud nuts loose ( be careful to keep up with all internal thrust washers/springs). Lay the end caps down, inside up. Saturate the wicking of the bearing with machine oil.
Reassemble the mother.
Point is, if the fan isn’t ru Ning up to speed, then it can’t move enough condenser air to cool the refrigerant, which means high head pressure, which means more heat in the compressor winding, which trips the compressor overload (embedded inside the compressor - not serviceable).