World Class RV Refrigeration Incorporated

Troubleshooting

RV Refrigerators can be difficult to diagnose, as some symptoms can be caused by different things, such as a bad thermostat, faulty electric heating element, insufficient gas (propane) pressure, a bad or weak 12 volt battery, etc. However, there are some basic signs of a faulty cooling unit. Among these are:

1) A strong ammonia smell inside the refrigerator. This indicates a rusted out evaporator.

2) A yellow residue around the gas burner on the back of the refrigerator. This indicates a crack in the boiler.

3) A gurgling or perculating sound coming from the refrigerator. This indicates a hole in the system.

If you experience any of these symptoms, then it is time to replace your cooling unit. However, not all symptoms are as easy to diagnose. For instance, a blockage inside the cooling unit will not show up as easily. Your refrigerator will slowly cease to function. You might notice that the refrigerator compartment is not as cold, or even warm, while the freezer compartment stays cold. This usually is caused by a bad cooling unit, but, it can also be an indication of another problem.

The best way to check a cooling unit, if you do not have one of the obvious problems listed above, is to bypass the thermostat and all of the electronics and run the refrigerator direct. To do this, you will need to trace the wires from the 110 volt heating element and unplug them from the control board. Next, you will need to take an extension cord (a heavy one) and cut the end off of it. Strip the wires back on the extension cord, and wire the 110 volt element to the extension cord. Plug the extension cord into a household outlet, level the refrigerator, and let it run for a few hours. If the unit heats up and no cooling takes place, then you have a bad cooling unit. If the refrigerator cools in both the freezer and refrigerator compartments, then the cooling unit is good and you have another problem. It really is that simple.

For more information, or to talk to one of our technicians, please contact us at 1-866-977-0877, toll free, from 8 a.m. to 4 p.m., Monday through Friday, Central Standard Time.

Seal the Cooling Unit

An overlooked part of installing your new cooling unit is sealing the unit to the cabinet.

By not sealing the perimeter of the replacement cooling unit, you are allowing hot air from the back of the refrigerator to seep into the refrigerator cabinet. This will give the false impression that your new cooling unit does not work.

To seal the unit, we recommend the use of putty tape around the foam perimeter of the unit, as well as around the edge of the aluminum cooling fins that go inside the refrigerator. Also, an application of aluminum foil backed hvacr repair tape around the edge of the unit is highly recommended.

Ventilation

One of the most important, but overlooked, aspects to the proper operation of an rv refrigerator is ventilation.

RV refrigerators use heat to make things cold....you boil liquid ammonia. This produces a tremendous amount of heat in the back of the cooling unit. This heat MUST BE removed for a cooling unit to operate.

The typical ventilation setup consists of a pair of vents on the outside of the rv...one on the lower sidewall, and usually one on the roof. This setup uses the principal that hot air rises and draws cool air over the coils. This works well in most cases, however, in the case of larger capacity refrigerators, there needs to be an additional mechanical force to drive the hot air out faster. Hence the addition of 12 vdc auxilliary fans to force the air out.

These fans are an absolute necessity in the case of both vents being located on the sidewall, such as in the case of a slide-out. The hot air cannot rise out of the roof vent as it is not there, so this hot air pools around the refrigerator and chokes the cooling unit down. The fans, again, force the hot air out of the side vents thus allowing the cooling unit to work properly.

In the case of larger refrigerators, such as the Dometic NDR1292's or Norcold 1200's, these fans are usually installed at the rv manufacturer along with a baffle system between the refrigerator and outer wall of the rv. This baffle system is designed to increase airflow when used in conjunction with auxilliary fans, as these refrigerators require high volumes of cool air flowing over the cooling unit.

If your cooling unit is not working, check the ventilation system first. Make sure there is nothing obstructing the airflow...this is a favorite place for dirt daubers to build a nest. If you have fans, make sure they are working.

DOMETIC

OR

NORCOLD

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1-501-977-0833