Add a Cooling Fan to your 3 way RV Refrigerator

Some gas /electric RV fridges can have trouble keeping cold on hot days and there is a fairly simple modification you can do to improve their performance.  Gas electric or absorption style fridges use an upper and lower vent to remove heat from the rear of the fridge using convection currents.  Cold air enters the bottom vent and is heated as it passes through the fridge cooling fins, then rises and exits through the top vent.  The top vent is best located at roof level however some installers mount the upper vent level with top of the fridge in the RV side wall, this works but not as well as a roof vent.

One easy modification you can do to speed up the air flow and the cooling process is to add a 12 Volt Cooling Fan to  draw the air past the cooling fins.  In the picture below I’ve purchased a  4 3/4” or 120 mm computer cooling fan and attached it to the inside of the upper RV fridge vent, with 4 cable ties.

Computer Cooling Fan Attached to Vent

120 mm Computer Cooling Fan cable tied to Upper RV Fridge Vent

This is very easy to do and from the outside of the vent you barely notice the ties (picture  below).  This is just a no name brand fan, however Dometic and Valtera make similar fans.  This fan only draws 0.2 of an amp and its so quiet you can’t hear it running.

By placing the cooling fan on the upper vent and having it draw the air past the cooling fins, it creates a slight low pressure area at the rear of the fridge.  This low pressure area might also help to reduce the chances dangerous carbon monoxide gas from entering the living area from the rear of the fridge.

Dometic fridge vent.

Upper RV Fridge Vent with Fan Attached to the Inside. You can just see the zip ties.

There are a couple of ways you can set these fans up, one way is to use a small thermostat switch and attach it to the burner tube on the rear of the RV fridge.  This setup allows the fan to come on at a certain temperature then turn off again when the temperature has reduced.

The way I set my fan up was with the use of a manually operated switch, pictured below.  I  ran some twin conductor cable,  found a 12 volt power supply, ran the red cable from a fuse and then too the switch and to the fan.  I attached the red and black cables to the cables coming from fan, then ran the black cable to a suitable ground.  I did have to drill a couple of holes to run the cables, note that when running cables through the walls of the fridge cabinet the holes should be sealed around the cables with Sikaflex as this stops dangerous gases from entering the RV living space.  The rear of a RV gas fridge needs to be sealed from the living area.

 Fridge Fan Switch.

Switch to Manually turn on Fridge Fan

Electrical cable.

Twin Conductor Cable.