There are tradeoffs associated with a more powerful & power hungry fan. A fan inside the fridge will not add cooling due to flow of air, but will tend to even out the temp within the fridge. This suggests that a relatively small fan that can move 3 cu ft per minute (the size of a large RV fridge interior) will turn over all the air in the fridge 60 times per hour.I wish I could find a better fridge fan. I have that one and have had several others too. They are all anemic. Does anyone know of a better fridge fan?
A external fan in the fridge cabinet just needs to exhaust the air heated by the fridge heat pump action. This is an even smaller volume of air to move than inside the fridge but it’s purpose is exhaust the heated air from the rear of the fridge & replace it with ambient temperature air to reduce the energy required to maintain the fridge internal temperature. The volume of air in the fridge cabinet outside my fridge is about 2 cu ft. I had a fan that moves 25 cu ft/min for less than 0.2 amps so I mounted it & wired it to the reefer fan circuit. I can feel the hot air being exhausted by the fan when it is running. Ambient air replaces the air heated by the running fridge about 12 times per minute which should be sufficient. A fan similar to mine is like this one:
https://www.amazon.c..._hps_bw_c_x_4_w
It would be best to wire it up so the fan runs only when the fridge runs, but I run mine only when the ambient temperature is above 60 deg F or so.
Paul
