Why Is My RVs Roof Air Conditioner Only Blowing Warm Air?

by Roxanne
(Corvallist, OR, USA)

We purchased a used AC which we were told blew Cold Air. However, after installing it, it only blows warm air. What should we check to see if something wasn't connected correctly or possibly damaged in shipment? The AC is a Coleman Model #67590707.

ANSWER: Greetings Roxanne thanks for submitting your question on our Ask An RV Question Page.

I am afraid that there is not much that a do-it-yourselfer can do to fix an RV Air Conditioner. There are several reasons why your A/C is blowing warm air.

1. May need to be recharged with Freon and checked for a leak (the old Freon had to go somewhere). The lack of Freon could be due to damage caused during shipping or it could be a pre-existing problem with the unit before you bought it.

2. The compressor of the air conditioning unit could be bad. Again, this could have been a pre-existing problem with the unit.

3. It could be a wiring problem, but the fact that the fan is blowing means that you got the fan wired right.

4. It could be a bad electronic control board in the A/C unit.

5. It could even be caused by a bad thermostat.

As you can see there are many reasons that the Air Conditioner is blowing warm air. Unless you are properly trained and equipped to repair the A/C unit, it will end up being a trial and error situation. If you attempt to repair it yourself and do the repair incorrectly you can cause further damage to the air conditioning unit itself or even cause damage to your RV's electrical system.

This is a job that is best left to an RV Technician that is trained and qualified to do A/C repairs. The best thing I can suggest is to take it in and have it looked at and get an estimate of the repair costs. If you find out it was a pre-existing problem, you might want to contact the seller to see if you have any recourse with them.

Happy RVing

RVing Al