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These hints pertain to electric/propane fridges only and not residential versions.
When troubleshooting fridge operation it is very helpful to observe what is working and what is not. The propane section operates differently from the electric side so if only one side is not working, some components can be eliminated as the source of the problem. Try to download a service manual for your model fridge as it will definitely help. It may have a flowchart to follow for troubleshooting.
The fridge uses 12 volts for control in both modes of operation. When in electric mode 120 volts MUST be available for operation. Verify that the fridge circuit breaker is not tripped. Odds are the fridge would not even attempt to go into electric mode if 120 volts is missing. Also, it wouldn’t hurt to verify that you have a good 12 volts (from the ground wire connection) at the power connection to the fridge.
Propane side OK, electric side fails – The electric side uses a 120 volt heating element to heat the ammonia mixture that results in cooling. The heating element should probably be the first thing checked. This can be done with your test meter in one of 2 ways – voltage measurement or resistance measurement.
Once you have located the heating element’s wiring, you can set your meter for resistance and place the leads across the wiring (might have to get creative on how to get to the wire inside conductor). Very important – do not try taking a resistance measurement with any power applied to the fridge as you would probably destroy your test meter. If the heating element reads open (infinite ohms), replace it.
The other test would be to check for 120 volts across the heating element when in the electric cooling mode. If 120 volts is measured across the heating element but yet it is not heating up, the heating element is bad.
If the heating element measures OK or the 120 volts is missing when in electric cooling mode, this could point to a board failure or, if present, a relay that the board controls that passes the 120 volts to the heating element.
Electric side OK, propane side fails – Verify that propane is available. This can be done by firing up a burner on your stove. Some items in the propane operation: spark ignition, gas valve, burner, chimney. Follow the troubleshooting flowchart in your downloaded service manual to narrow things down. You may be able to measure voltages at the various components. Also, the burner needs to be clean and any gas orifice jets open.
If the ignition has initiated a spark but yet the burner fails to ignite, there may be air in the system, no propane, gas valve problems etc. The ignition sparking tells you that the board is at least trying to light the burner.
Poor cooling propane and electric – This may be a common complaint. First off, these fridges need to be level to operate. If you are trying to operate it on a slope, it won’t cool properly and you could damage the cooling system.
You need to determine if it is trying to cool, meaning the burner is on or the electric element is receiving voltage. This is important because it will point you in the right direction. The easiest way to see if it is trying to cool is to operate in propane mode and look for a flame. If the flame is present, it is trying to cool. No flame may mean the fridge thinks it has reached the desired temperature and has cycled off.
Trying to cool – If your fridge is trying to cool but not working very well you may have a buildup of heat in the rear of the fridge. Many fridges have built-in exhaust fan(s) at the top that come on when excess heat is detected. These fan(s) pull air in from the bottom and exhaust it out the top and are typically controlled by a thermal switch. There have been a number of instances where these fans have failed. If you have downloaded a service manual for your model it should indicate whether you have these fan(s) or not. It also may have a troubleshooting flowchart for poor cooling. If you can get to your thermal switch you can jumper it to see if the fan(s) come on. These fans operate on 12 volts.
When cooling on gas the flame should look clean and stable. Problems can result if the burner or flue is clogged/dirty. When cooling on AC some fridges may have 2 heating elements and one may be bad. The service manual will give information on this.
If you see a frost buildup on the rear tubing it may indicate an ammonia blockage. Try tapping the tubing with a block of wood to clear the blockage. There have been reports that this has solved the problem and the fridge returned to normal cooling.
If everything appears normal there may be one last thing to try. It is called “burping the fridge”. Apparently it is a procedure to get rid of possible bubbles in the ammonia. I am totally unfamiliar with this but wanted to include it in this troubleshooting section. For information on burping the fridge, do a Google search for “Burping RV Fridge”.
Not trying to cool – If your fridge has cycled off, meaning it thinks it has reached the temp you have set, you may have a problem with a thermistor. This is the electronic device, often attached to the fins inside the fridge, that senses the inside temperature. The control board reads the thermistor and turns off at a certain reading. If the thermistor is bad it may cause the board to shut off cooling before it should.
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Jim
Retired electronic technician (45 years in the field)
2017 Greyhawk 29W (solar & many other mods)
wife (maybe I should have given her top billing)
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Linear Mode
