Steve Savage submitted this article to RVtravel.com when he was a Master Certified RV Technician with Mobility RV Service.
One of the calls we often receive during hot weather focuses on complaints about air conditioners needing Freon (more correctly, refrigerant) or a concern the AC is not working as well as it should.
Here is a simple test you can do at home or in the campground to make your own assessment using nothing more than your kitchen thermometer – and possibly save a service call.
Set your unit to “cool” and let it run continuously for at least 20 minutes, then with your kitchen cooking thermometer do the following:
1. Take the air temperature at the return where the air goes back into the unit, normally the rectangular opening with the filter in the ceiling. Insert the probe and write down the temperature.
2. Go to the outlet farthest from the unit where the air comes out and again take a temperature reading and write it down.
3. Now subtract the lowest number from the highest number.
4. If the result is in the range of 18-25 degrees, that is as much as the air conditioner is capable of and there is nothing that can be done to increase the output. It is dropping the incoming air temperature on average 20 degrees – that’s it.
Run your RV air conditioner with only a small portable generator. Yes, it’s true!
If your air conditioner output falls within that range and you are still too warm, you either need an additional air conditioner or a bigger air conditioner. You will get a value lower in the range when humidity is high, as the air conditioner has to dump humidity before it can reduce air temperature. When humidity is lower, the air conditioner can expand more of its energy reducing the incoming air temperature.