fridge cooling fan?

[QFour]

It's just occurred to me that this might be a use for the unused "load" terminals on my MPPT solar controller - but having googled it, there are differing explanations as to how the "load" supply works, with most saying that it's not of any use in the motorhome.
If it is supplied from the unused energy from the solar panel after fully charging the batteries, which would otherwise be wasted, then it seems to me it would be ideal for powering the fridge vent fan, as it would be available during periods of sun when the ambient temperature is likely to be higher. However, if it's going to reduce the charge going to the batteries, or even worse use some of their power, it's probably not a worthwhile option.
Perhaps some of the knowledgeable contributors on solar could advise?

No reason why not but it just complicates things a little. The fans you fit will take hardly any power. They can however be noisy especially on full power. So I have a switch on mine which can switch them on, off, auto and half speed. On half speed you cannot hear them running but they do increase the flow of air through the back of the fridge. If you play around with resistors in the circuit you can have them running at half speed or you can wire them in parallel with each other or series. If you cannot hear them running on full power then just switch them on and off or do it automatically and try something like HERE

 

[oppy]

Sorted, I managed to get a couple of ex Maplin stock pc fans for nuppence and fitted them. I took the power from a silly little foot-well light via a remote switch and voila instant cooling that really does work, I'm impressed, and as a bonus, the blasted things light up too, ah well, but the fridge works whilst the weather is hot, so that is all that matters

 

[oppy]

And they work too

 

[Deleted member 62288]

It's just occurred to me that this might be a use for the unused "load" terminals on my MPPT solar controller - but having googled it, there are differing explanations as to how the "load" supply works, with most saying that it's not of any use in the motorhome.
If it is supplied from the unused energy from the solar panel after fully charging the batteries, which would otherwise be wasted, then it seems to me it would be ideal for powering the fridge vent fan, as it would be available during periods of sun when the ambient temperature is likely to be higher. However, if it's going to reduce the charge going to the batteries, or even worse use some of their power, it's probably not a worthwhile option.
Perhaps some of the knowledgeable contributors on solar could advise?

You're idea will work. That would be a good use for the load terminals.

My Victron MPPT controller manages the leisure batteries of 470Ah first. Then diverts the charge to the load terminals.
On my load terminals, I have hung a Sterling B2B charger which to the engine battery so all my batteries are optimally charged. Works very well.

By mid-late morning my leisure batteries are back up to 104% and the engine battery is content.
This means that I then have an idle solar system for the rest of the daylight hours.

There must be a use for this free energy.

james

 

[oppy]

You're idea will work. That would be a good use for the load terminals.

My Victron MPPT controller manages the leisure batteries of 470Ah first. Then diverts the charge to the load terminals.
On my load terminals, I have hung a Sterling B2B charger which to the engine battery so all my batteries are optimally charged. Works very well.

By mid-late morning my leisure batteries are back up to 104% and the engine battery is content.
This means that I then have an idle solar system for the rest of the daylight hours.

There must be a use for this free energy.

james

Much to technical for my poor old alcohol frizzled brain cell, so that said, it works and after being left on all weekend the batteries still read 13.7v and the white wine and beer are still nicely chilled, which is the most important bit.
Seriously though, after the advice from my friends here, we are more than satisfied with the results and chuffed that it actually works

 

[izwozral]

Heat rises so top vent blows out!

The last MH Rimor showed a clear drop in temp with fan running over a one hour period by 1.6 degrees despite not moving the setting on the fridge. Not an exact science but the indications are pointing in the right direction. For the cost of a fan, bit of wiring and a hour of labour [even for this numpty}, it makes sense to fit one if spending time in hot climes, i.e. UK!!!!.

Bet you never would have thought that a few years ago?

 

[taximan]

Dometic sell their own fan kit which actually fastens onto the coils/pipes on back of fridge itself and points upwards blowing air onto the fins.