ROOF MOUNT AIR CONDITIONERS

The air conditioning on most RV's is on the roof. To work properly roof top air conditioners need maintenance, just like your home air conditioner.

The major difference in most split systems, like air conditioners found in homes, are designed to test and add freon as a part of the service. RV air conditioners are a hermetically sealed system. They are not designed to add freon.

Both of the major manufacturers of RV air conditioners advise in their service information that if the AC has a problem with the hermetically sealed system, the air conditioner or the system must be replaced. Most often the whole AC must be replaced. With this in mind, do not ever let anyone put valves in the system to check and add freon. These valves always leak and if there is a leak, there is a problem. It is best at this point to replace the air conditioner. The cost of doing the system replacement is close enough to a new air conditioner most people consider a new one. The average RVer can do a couple of things to maximize the efficiency and life of a roof top AC. They are:

1. Keep the filter in the return air intake clean. When the filter becomes dirty, the air flow over the cooling coils (evaporator) is diminished. This will impede the air flow which causes freeze ups. The transfer of cold is diminished. Keeping the fan on high speed is also important.

2. When using the air conditioner, check the voltage to make certain there is a minimum of 105 VAC to the system running the air conditioner. I like to see 108 VAC but the books say 105. Low voltage can cause heat in the compressor and the fan motor. Heat can tend to damage both of these. The explanation of the why, is a subject that is detailed enough for another total article. Just remember when you run an air conditioner with less than 105 VAC the potential to damage the air condition is very real.

Purchase a volt meter and use it. When the volt meter shows less than 105 VAC problems will result. Another thing about the volt meter is it must be accurate. Have someone who has a calibrated volt meter check it.

Air conditioners for RV's are very complex. If Rvers would only pay attention to the few concepts in this article, the chance of having problems with an air conditioner are greatly diminished.