@Pete C. Can you give more detail please - actual fan and controller, position and where you wired it in would be good. Any pictures? I can't say that we've ever had any issues with things being cold enough (even when the fridge is only set to 1 in hot weather) and nor has the compressor kicking in ever disturbed us but, as
@JOG says, it might well help to extend the life of the fridge. Cheers in advance.
Sure.
First photo shows where the fridge is. The Dometic fridge has a fan on the left hand side, which pushes air out to the left. Originally, I cut a 120mm hole in the side of the left hand panel surrounding the fridge exactly opposite and stuck a 120mm vent there, which should help a bit - this was 4 years ago.
Second photo shows the door flapped down above the fridge. The space is shallow due to the sink, and as you can see it has a fire extinguisher plus fire blanket in there, plus a new thermometer with remote sensor to measure the temp above the fridge - this is temporary.
You can also see the homemade voltage regulator (LM317 based) in a black box with a control knob. This is fed from the fuse box, and the variable voltage output goes to the fan.
The fan is an generic 80mm model which is now cable tied into 80mm square slot cut into the 120mm vent mentioned above. Getting a photo of that is difficult as it is behind the drivers seat.
I was going to go with thermostatic control, but that just added complexity that we didn’t need.
It’s not been the best weather to test it, but got the interior up to 32°c with the heater today, and loaded the fridge. The the space behind the fridge was another 5° or so above that. As soon as the fan is turned on, the temperature drops quickly, so works well enough for me.
We have never had the problem that food isn’t cold enough (always gives us ice cubes for G&T), but very aware that the fridge has to work really hard in Southern Europe.
Hope this helps,
Pete