Fridge top vent cooling fan modification. (1 Viewer)

[MitchandJenny]

I know this has been raised before, but is there an "up to date" way to fit a couple of computer type fans to the top vent ??
Our Autotrail Tracker fridge was working really hard to keep cool when on gas and got hot enough to distort the top vent. I've just had it serviced, as its 3 years old (and we run mainly on gas).
I'm off to Maplins next Tuesday, so will ask there, but hope someone on here has done it.
I want the fans to cut in automatically at anything above 25 Deg C and out again when the temp drops below 40 - 50 Deg C (ish).
I know there is a complete kit at about £40 from Rainbow conversions, but that seems a bit "steep".
All help gratefully received.
Yes I know, I'm tight ! ! !
Mitch.

 

[JackieP]

I found a fan at the tip and fitted it to the fridge vent with four (small) screws. I ran a wire to a switch inside that I turn on if the weather is hot (it hasn't been off for six months).

It cost me the price of the rocker switch and it's probably the single most useful thing I've ever fitted in the van. The fridge is now rarely off the minimum setting, compared to last year when it was never off the highest setting and I had to prop open the vents just to get a bit of air in to stop the milk going off.

 

[TheBig1]

Hi Mitch, the current thinking is to use an adjustable temperature comparator board. basically a digital thermometer on a pcb that you can set on and off temperatures. Only costs under £2.30 delivered and work very well


simple to wire up and pick up a 12v supply at the back of the fridge

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[DL42846]

Can anyone tell me what the switch does under the red light? I always thought it was a fan switch .

 

[The Nomad]

As they use almost no electricity, why not just wire it up to any 12volt supply from the leisure batteries via a little on/off switch.

We actually have a twin-fan setup with an accompanying little control panel with an integral thermal switch option (plus and always on, or always off option).

From memory I think it was about 40 euros as a "proper" system, from a motorhome spares dealer in France. This was about 6 years ago now.
Piece of cake for me to self-install, and has been utterly fantastic at helping to keep fridge/freezer cold when parked up on gas as we are almost all the time. I reckon we use less gas now than we used to before I fitted it.

Whether you go the self-build or buy complete route, I strongly endorse having such a fan vent assist option.

 

[Alistair33]

Can anyone please fill me in on the reasoning of fitting a fan and where. It would be fitted, be top vent accessed form the outside?

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[TheBig1]

Can anyone please fill me in on the reasoning of fitting a fan and where. It would be fitted, be top vent accessed form the outside?

the reason is to increase the airflow behind the fridge. absorbsion fridges work in a different way to houshold compressor fridges in that they use heat to circulate the coolant. in very hot temperatures the efficiency decreases dramatically. fitting a couple of small fans to the inside of the upper vent, sucking air out, induces air to flow in via the bottom vent and across the heat exchanger

 

[Zigisla]

Can anyone tell me what the switch does under the red light? I always thought it was a fan switch .View attachment 161144 View attachment 161145

I have a switch with a similar symbol on it and it is shut off a the tiny heater that is used to stop condensation build up behind my LCD panel when not on EHU as it conserves your battery a bit.

 

[955matt]

Very easy to fit , and very cheap off e-bay for the fans and the adjustable switch. The switch under the red light is for the heated seal around the door which is to help stop condensation

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[PhilandMena]

You could in the short term wind your awning out a couple of feet or so to put the top vent in more shade.

 

[FJmike]

You could in the short term wind your awning out a couple of feet or so to put the top vent in more shade.

Provided your fridge vents are on the same side as your awning

 

[Mikey RV]

Can anyone tell me what the switch does under the red light? I always thought it was a fan switch .View attachment 161144 View attachment 161145

That switch when on heats the frame to get rid of the condensation around the fridge frame, not sure how long you can leave it on though.

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[Nik]

Hi
I haven't looked at the practicalities of fitting a fan yet but do you have to remove the fridge to fit the fan and where do you take the power from?
Sorry, I'm bit of an electrical noddy.
cheers
Nik

 

[Riverbankannie]

do you attach the computer fans to the inside of the removable vents on the side of the MH? If so how do you prevent water, from either rain or washing, getting on them?

 

[MitchandJenny]

Thanks JackieP, I take it you found a PC cooling fan. ?
Mitch.

Hi Big1. Isn't the 12 volt supply at the back of the fridge ignition controlled ?? for when your driving ??
Also, why are the spec figures all minus ( -50 to -100 ) ?? And does the shiny probe go into the hot area at the back of the fridge behind the top vent ?? Being a bit "thick" I know.
Mitch.

Thanks Nomad.
Mitch.

I do do that awning thing PhillandMena. But thanks.
Mitch.

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[TheBig1]

Hi
I haven't looked at the practicalities of fitting a fan yet but do you have to remove the fridge to fit the fan and where do you take the power from?
Sorry, I'm bit of an electrical noddy.
cheers
Nik

you dont normally remove the fridge but sometimes it needs sliding forwards a couple of inches to pick up power from the permanent 12v connection (if available)

do you attach the computer fans to the inside of the removable vents on the side of the MH? If so how do you prevent water, from either rain or washing, getting on them?

you mount the fans inside thevents an inch or so back. a few splashes of water is fine but you never soak the vents anyway

Thanks JackieP, I take it you found a PC cooling fan. ?
Mitch.

Hi Big1. Isn't the 12 volt supply at the back of the fridge ignition controlled ?? for when your driving ??
Also, why are the spec figures all minus ( -50 to -100 ) ?? And does the shiny probe go into the hot area at the back of the fridge behind the top vent ?? Being a bit "thick" I know.
Mitch.

Thanks Nomad.
Mitch.

I do do that awning thing PhillandMena. But thanks.
Mitch.

Mitch as above, most fridges now have a permanent 12v feed for the light and control panel
the thermostat works -50 to +100, isnt chinglish wonderful
the temperature probe can be either inside the vent or using different temperature range on the heat exchanger which is always hot

 

[Lenny HB]

This is how I did mine a couple of weeks ago, post #113, carry on down a few posts and there are links to the bits I bought.

 

[JackieP]

Thanks JackieP, I take it you found a PC cooling fan. ?
.

Yes. It was only a small one but it's made a massive difference. Just you wait.

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[magicsurfbus]

Our last MH had a simple solar charge controller added to it, and there were a couple of spare 12v terminals on it, with a built in switch. I attached an old computer cooling fan to the inside of the upper fridge vent and wired it to the terminals on the controller.

The issue I had with a DIY installation was the fan created an irritating buzz that resonated in the MH's wall. Cushioning it on bits of foam or sealant worked up to a point, but if a bought system had been quieter I'd have gone for it.

 

[DL42846]

That switch when on heats the frame to get rid of the condensation around the fridge frame, not sure how long you can leave it on though.

I'm no expert here, but I leave mine on all the time the fridge is on. Sometimes when we are wild camping it stays on for three/four days at a time. Morning noon and night.

 

[jezport]

Ive found a 12v 120mm fan with a built in heat probe that speeds the fan up as the heat builds up.
Im going to try it out next week, and will report back

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[MitchandJenny]

you dont normally remove the fridge but sometimes it needs sliding forwards a couple of inches to pick up power from the permanent 12v connection (if available)

you mount the fans inside thevents an inch or so back. a few splashes of water is fine but you never soak the vents anyway

Mitch as above, most fridges now have a permanent 12v feed for the light and control panel
the thermostat works -50 to +100, isnt chinglish wonderful
the temperature probe can be either inside the vent or using different temperature range on the heat exchanger which is always hot

VERY many thanks Big1.
Grand job mate.
Mitch.

 

[MitchandJenny]

Jezport.
Many thanks.
Mitch.

 

[Nik]

Hi @TheBig1 and @Lenny HB
Thank you both for your informative and useful posts.

@Lenny HB .... I've just looked at your photos on you previous thread and the blue wire is connected to a black box. Is that the connector to the digital readout thingy?
and did the fans come with the correct connecting wires?
Thanks again both.
Very best regards
Nik.

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[Lenny HB]

Hi @TheBig1 and @Lenny HB
Thank you both for your informative and useful posts.

@Lenny HB .... I've just looked at your photos on you previous thread and the blue wire is connected to a black box. Is that the connector to the digital readout thingy?
and did the fans come with the correct connecting wires?
Thanks again both.
Very best regards
Nik.

For convenience, I used CAT5 cables the black box is a CAT5 connector just allows 2 cables to be plugged together just so I can remove the grill easily. You need to get 5 wires to the controller, neg, pos, switched pos, and the 2 sensor wires. The controller is in the bottom of the wardrobe next to the consumer unit. On my previous van I used a cheaper PCB controller an put it in a plactic box and left it behind the fridge but I still ran a cable into the van to an on/off switch, one of these.
The fans are 4 wire ones you need to use the black (neg) and yellow (pos) for full speed operation.

 

[Geo]

Never fitted one so dont know the answer
But would these fans not be ideal candidates for the "Load" section of you Solar Controller ?
After all if its hot your batts should be fully charged and you have free electrickery there

 

[TheBig1]

Never fitted one so dont know the answer
But would these fans not be ideal candidates for the "Load" section of you Solar Controller ?
After all if its hot your batts should be fully charged and you have free electrickery there

absolutely fine to run of the solar load circuit

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[MitchandJenny]

It sounds a bit of a "faff", so I may just go down the route of using a PC cooling fan with an on off switch wired through a thermal micro switch.
Lazy AND tight !!! Terrible combination...
Mitch.

 

[MitchandJenny]

OR, I may just put my hand into my VERY deep pockets and buy the ready made "thingy" from
Rainbow Conversions..
The trouble is,, is that it draws 6amps ! ! ! And that is the output from a solar panel negated ! ! !
Oooooooh flipping ek... Back to the drawing board....
Mitch.

 

[Lenny HB]

OR, I may just put my hand into my VERY deep pockets and buy the ready made "thingy" from
Rainbow Conversions..
The trouble is,, is that it draws 6amps ! ! ! And that is the output from a solar panel negated ! ! !
Oooooooh flipping ek... Back to the drawing board....
Mitch.

HOW MUCH!
The fans I used say 0.25amp each but in use they don't draw that much.

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