Answers to questions about RV Repair and Maintenance from RV expert Dave Solberg, author of the “RV Handbook” and the managing editor of the RV Repair Club. This column appears Monday through Saturday in the RV Travel and RV Daily Tips newsletters. (Sign up for an email reminder for each new issue if you do not already receive one.) Today Dave discusses fixing a propane fridge that doesn’t cool.
My propane fridge lights up but does not get cold. It’s likely sat for a long time unused and probably not level. Are there any DIY tricks I can do at home to revitalize my fridge without paying a professional (funds are limited)? —Jason
While it is important to have the refrigerator level when it is running, you will not do any damage to the cooling unit being unlevel when it is not in use.
How a propane fridge works
The heat source (flame in the LP mode) heats a solution of hydrogen, ammonia, water, and sodium chromate from the burner vessel. That turns into a vapor and travels up the flue to the evaporator coil in the freezer compartment. There are a series of chemical reactions and the solution turns back to liquid and must make it’s way back down the zigzag cooling unit to the burner vessel. There are no moving parts and no pumps so the liquid flows by gravity. If the unit is out of level, it will pool on one side and will heat up, which will cause the liquid to thicken, flake, and eventually block the tube. If it’s not running, there is no heat.
Does your unit also run on 120-volt power? If so, try that mode and see if it cools, as it will use an electric heating element rather than a flame. If it does cool, then it is something in the LP mode. But if it does not, then you most likely have a blocked cooling unit. There are some dealers and service centers that claim to be able to cut the blocked part out and reinstall a clean tube. However, I have not had any experience with that.
Try taking the propane fridge out
You can also try taking the propane fridge out and tapping the blocked area with a rubber mallet. You will see the coil is discolored and paint is burned off due to the heat. Also, you can plug the unit in and use a laser temperature gun to identify the hot spot. Otherwise, it’s a new cooling unit or new refrigerator.
If by chance the unit works on electricity, or you don’t have an electric mode, try cleaning the burner assembly.
Use an air compressor and air gun as shown in the photo and blow out the tube and flue. You might need to remove the metal housing that protects the flame from wind. Wear safety glasses as you will have a ton of dust and soot flying out. This will allow a better LP to air mixture and a better flame.
Check the flame
After this, run the unit and verify the flame is tall and blue and not jumping around. Also make sure it is staying lit for the entire operation. If the flame goes out quickly, you have an issue with the thermal coupler. That is just above the flame and creates a closed connection telling the module board there is flame so keep the gas valve open. If it does not have a tall enough flame, it tells the board to shut off the valve. If the flame does not stay lit, it could also be low or sulfated house batteries. Try putting a battery booster on and see if it stays lit.
Read more from Dave here.
Dave Solberg worked at Winnebago for 15 years developing the dealer training program, as marketing manager, and conducting shows. As the owner of Passport Media Creations, Dave has developed several RV dealer training programs, the RV Safety Training program for The Recreation Vehicle Safety and Education Foundation, and the accredited RV Driving Safety program being conducted at rallies and shows around the country. Dave is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club.
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