DIY RV Air Conditioner Maintenance
It won’t be long and we’ll be cranking up the A/C inside our RVs. That may lead us to wonder whether an RV A/C unit is operating properly. To check the effectiveness of the refrigerant in a rooftop unit, use a probe-type pocket thermometer to measure the difference in temperature between the cold-air supply and the return air.
Begin by running the air conditioner on the “high cool” or maximum setting for at least 30 minutes. Close all the windows and vents, and open all air conditioner ducts. Position the thermometer directly in the flow of the cool air being discharged into the RV. After the temperature stabilizes, note this reading.
Next, place the thermometer probe in the path of return air to the unit. The return air path goes directly through the filters. Usually, the probe can be inserted into the filtering element. Note this reading as well. In ducted systems with multiple return air vents, measure the temperature at the return air vent closest to the main rooftop unit.
On the “high cool” setting, a temperature differential of 18 to 22 degrees Fahrenheit indicates a system with the proper amount of refrigerant. In areas of high humidity, however, the temperature differential may be somewhat less, but 18 to 22 degrees difference is the goal. Most RV air conditioners are simply no match for extremely high temperatures, which is why many larger RVs are outfitted with multiple units.
If the temperature differential is substantially less than 20 degrees Fahrenheit, contact an RV service facility for further troubleshooting. A slow refrigerant leak may exist somewhere in the closed system, or a faulty component may have reduced the overall cooling efficiency.
To learn more about what RV owners can do to maintain their A/C units, check out this article from a past issue of Family RVing. (Please note that you must be logged into your FMCA account to view the full article. Members receive full access to every article on FamilyRVingMag.com.)