3 fans, that's posh!

I'm a two fan man. all automatically temperature controlled...

IMG_7935.jpg - Bild entfernt (keine Rechte)

Just a warning that the Velleman kit (as used on Aaron's fridge fan project page above) is no longer available. Velleman have an alternative (Whadda) pre-assembled board available through their website. Around £8.

I'm about to build my own twin fan system - I bought two unused, very low noise, 12v, 120mm computer fans (Acoustifan AFDP-12025s) and a piece of 2mm aluminium to cut out, bend at the base and then attach by pop rivets to the "baffle" inside the fridge vents (the air is much better directed on the more modern RM5330 fridges).

I have looked at many designs, including Aaron's and John England's, the official Dometic one (very expensive) and the Reich one that I had on my last Eriba (seemed to work well, but also quite expensive). The Dometic installation guide is very useful for the best place to attach your thermal switch on the back of the fridge.

This site is also useful, with some DIY building involved, if you so wish:
https://the-trudgians.com/fridge-vent-fan-mk2/

You may find my approach of use, SImon:

Fridge fan upgrade - another approach

That also used computer fans and a witty little circuit board to control it all...

hth..

A valid approach, Colin.

I think the way mine behave is that as soon as the cycling coolant in the fridge reaches 40C, then the fans turn on (at minimum speed0. That is unrelated to any other temperature. As the temperature increases in the 'flue', the fan speed is raised in response. So it isn;t playing 'catch up' as it were, but should be keeping up with the cooling requirement as it develops..

Whether that is any better or worse than your approach (or the same!), I don;t know...