Bruce Bernhart RV FAQ's

Part of the Bruce Bernhart Websites

Original articles plus the "best of the web" on RV care and maintenance by RV writer/expert Bruce Bernhart

RV Care and Maintenance Topics: Air Conditioners

In Minnesota, Bruce Bernhart has been an RV and camping enthusiast since the mid-1980's

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Look for other Bruce Bernhart RV care and maintenance topics on Articlesbase and Ezinearticles and the Bruce Bernhart Blogs!

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Some Additional (and much more technical!) Installation Troubleshooting Tips:

If the Air Conditioner is still not functioning and both 12VDC and 115VAC are present and accountable at their
proper locations the problem is located in the upper unit. If the correct 115VAC connections are NOT made at the 9 pin connector plug after12VDC power is applied to the Low Voltage Terminal Strip; the problem is in the Printed
Circuit Board with one exception as described below. The low temperature freeze thermistor could open the
compressor relay on the Circuit Board if the Air Conditioner Evaporator Coil starts to freeze. If this switch is open
you would still have 12VDC at terminals Y and B, but no voltage would be present at terminals 1 and 3 in the High
Voltage 9-Pin Connector. The Freeze Thermister opens if the evaporator coil temperature drops below 32 degrees
and closes at 55 degrees. The probe end of this switch should be found pushed into the fins of the evaporator
coil and the wires are hooked to the Printed Circuit Board. It is OK to remove the thermister wire from the Board
and jump around these terminals fore diagnostic purposes. If the Air Conditioner compressor unit is running
and NO VOLTAGE is found between terminals Y and B on the Low Voltage Terminal Strip the Printed Circuit
Board must be replaced. The compressor relay has evidently welded shut.

In conclusion, you can save a lot of time if you get in the habit of going immediately to the ducted control
box assembly for trouble shooting purposes. There in a matter of minutes you can tell if the problem is
in the Thermostat, the Printed Circuit Board, or the Upper Unit.

Don't forget to check your A/C fluids. Take a walk around the condensing unit of your RV air conditioner. Do you see any signs of leaking? If you do see liquids coming out of the condensing unit you likely have a leak with your condensing fluid or freon. If this is the case, you will need to stop the leak and replace the air conditioner fluids appropriately to return the unit to a cold air flow.