Wiring a refridgerator vent fan

On my popup, I wired a couple of computer fans (12 volts) to the 12 volt that powers the fridge...never used the 12 volts anyways, just gas and 120 volt...I mounted them to the upper part of the outside plastic grill blowing outward. I slipped a 15 amp fuse in the spade connector, so it would be fused. Would just pull it apart when I didnt need it, plugged it in when I did...worked good

Are the OEM fans working?

12V DC (+) power at lower module......4A fused line goes to a relay then to/thru fan thermostat then to fans.

You can pickup the 12V at module...run a separate fused line to an ON/OFF switch then to new fan(s) or install another thermostat to control the new fan(s)

A member here, Pianotuna, has recently added an internal fridge fan and lowered internal temps by 5 degrees and subsequently lowered the T-stat setting needed to maintain that lower temperature on hius absorption fridge

I employ a small 40mm Sunon 0.03 amp ~6cfm fan inside my 1.8 cubic foot compressor fridge and notice similar benefits. At only 0.03amps I leave it to run 24/7.

External fans should not be needed with a well setup absorption fridge in non extreme ambient temps. Well set up meaning not too much space behind the condenser, and a baffle so that normal convection currents cause adequate airflow over the condenser. I've seen links on this forum to diagrams of proper condenser airflow on absorption fridges, but cannot find them now. Perhaps somebody has the link bookmarked.

You can add a snap switch which will activate the fans at 110f and turn them off at 90f:
http://www.emersonclimate.com/en-US/products/products_a_z/furnace_ignition_control_gas_valve_ignitor_thermocouple/Pages/snap_disc_fan_and_limit_controls.aspx

Do note that while many will lump all these computer fans together, they actually vary extremely widely in their performance. Some make very little noise and move a respectable amount of air for little electricity consumed. Others, not so much.

Do note that Sleeve bearing fans, the cheapoes, do not last long in a horizontal position. You want dual ball bearing or fluid dynamic bearings in this orientation.

If you do not want to worry about a temperature snap switch, or do not really have a concern about a 0.05 amp draw, this fan moves 53cfm for 0.05 amps and is very quiet doing so.

This is the fan I have put onto my compressor fridges condenser, pushing air instead of pulling it, and it draws half the electricity as the provided fan, makes less than half the noise, and has a high static pressure rating, so the condenser's restriction in front of the fan blades is of little consequence, and fridge performance improved after this modification.

http://www.noctua.at/pdf/infosheets/noctua_nf_f12_focused_flow_web.pdf

Make a shroud so that all the air moved from the fan blades is expelled out the roof, and your fridge will behave better. IMO, too many people go through the motions of adding a fan, without optimizing the benefits from doing so. Positive displacement so no preheated air is recycled = Huge benefits.

I get the power for ours from the door light switch, one side is always hot as long as the fridge is on and I get the ground from the cooling fins using a alligator clip. :)

tvman44 wrote:
I get the power for ours from the door light switch, one side is always hot as long as the fridge is on and I get the ground from the cooling fins using a alligator clip. :)

I think OP is looking at installing additional fans in outside compartment

On my dometic, in the outside compartment there are two circuit boards. One is covered with a plastic cover and is on the left wall of the compartment, the other is on the "Floor" and as I recall not covered.. This is the "Connections" board.. I THINK it is from this board (I can go outside and look tomorrow if you wish) that has the power lead that feeds the interior light.. and that's what I tapped, power to the light.

No matter which board it is.. Identify that wire and you got it.