World Class RV Refrigeration Incorporated

Heating Elements

Heating elements are an overlooked and often misunderstood component of an rv refrigerator. They either work or they don't, right? Wrong. Too much or too little heat can damage the cooling unit, or cause it not to function at all.

A cooling unit is designed with a specific capacity of liquid ammonia. This amount is based on the requirements of the system, but is regulated by the capacity of the accumulator tank on the bottom of the cooling unit, right below the absorber coils, and the boiler assembly. When you look at this tank, you will see a stem or valve on the side of the tank. This is, of course, where the unit is charged, but it is also the level of the liquid ammonia inside the cooling unit. If you were to draw a straight line across the bottom of the valve to the boiler assembly, this is the liquid level inside the boiler. It is also the location of the heating element sleeves and where the boiler gets hottest. If there is a drop in the liquid level inside the boiler, either by running the unit out of level or by a heating element that is too hot thus boiling the ammonia too fast, the boiler assembly will get too hot and this will cause a blockage.

If the heating element is too cold, the liquid level inside the boiler will not generate sufficient ammonia vapors to maintain the cooling process inside the evaporator.

If, during installation of your new cooling unit, you discover that the heating element will not fit into the sleeves on the new unit, then it is very possible that the elements are bad. When a heating element starts to go bad, the ceramic inside the element has a tendency to swell. If this is the case, you will have to replace the element(s).

If you suspect that your heating element is faulty, a simple electical test meter will tell the tale. Set the meter to check the ohms of the heating element. Unplug the element from the control board and touch the meter leads to the 2 wires. Record the ohms reading, and call us at 1-501-977-0833 with the results and the make / model of your refrigerator. We will be more than happy to discuss these results with you.

Control Board

The control board is the brain of the refrigerator. It is also one of the most difficult components to diagnose. We have special tools that allow us to test a board, and would be happy to test your board free of charge if you want to ship it to us.

If you suspect that you have a bad board, remove the cover from the board and check the fuses. There are 2 on a 2 way refrigerator, and 3 on a 3 way model. These are typical fuses that can be found at any hardware or auto parts store. The propane circuit uses a 3 amp fuse, and the 110 volt circuit uses a 5 amp fuse.

If these fuses are good, then take your electrical test meter and check for continuity across the board. Ifthis fails, then you will have to replace the control board.

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