Fan on fridge box

hi Graham
I would run it any time the fridge is been used and the box is parked or travelling don't see why it would need to run if the fridge box lid is open because there would be enough circulation in that situation
cheers

Hi Graham,
I have dual fans in my fridge box. They turn on at 30 degrees and off at 26. Dont know really if the fans really contribute to any fridge efficiency.

The controller is available in kit form from Jaycar : HERE
Cheers
Alan

It would greatly depend on the type of fan and it's current draw. If it's only a low watt computer fan it could run most of the time without affecting the battery, as mentioned above a good idea is to have a temp switch on it. If it's just a metal box you could also look at lining it with some insulation which will greatly reduce the radiant heat directed at the fridge as it can easily get above 50 deg inside which will make the fridge run constantly on hot days as it will struggle to keep temp.

I don't have an electric one I have a solar powered exhaust fan on my alloy canopy to help draw out some of the hot air out.

Isn't the reason the fans are there, to change the air around the fridge so it doesn't stew in it's own heat which it is trying to dissipate? No good having heat from any source heating the fridge and it's condensor, so it works the hardest all the time and use far more battery than required.
As long as the fan running uses less AH than the AH used during the less run times it provides for the fridge then the battery is in front.
The use of a fan may even allow the fridge to freeze if it is cool enough outside in the enclosure.

I use a computer fan running full time with appropriate ducting to provide cool air to the fridge and it's condensor while it is in a vehicle. Vehicles get hot inside like fridge boxes do.

Who places their house fridge in front of the gas heater? Same effect as a box in the sun.