Adding cooling fan to refrigerator?

[Cummins12V98]

Our Dometic frig is the two door stile. It is in a slide out so it has a outside vent high and low. Inside the exterior wall and behind the frig at mid heigth are two cooling fans that come on when the computer tells them to. I made it to where the two fans run all the time. We stay in some really hot weather at times so I am wondering if it would help if I added a small cooling fan behind the top vent on a switch that I can turn on when it starts getting hot?

[wantabe351]

You need to install a 12v computer fan inside the frig to move the air over the cooling fins.....

[Cummins12V98]

Cummins12V98 wrote:

BarneyS wrote:
Posted for Cummins12V98,

Thank you Barney for posting these pics!

I noticed when I looked at the pics I needed to add insulation between the fans. Those two fans are what came on the rv. I installed the single one with a switch in the lower compartment. I aligned the single fan behind the upper vent slot in the access door and as close to it as possible.

For now I am running the single fan all the time and have the double fans still tied into the controll board. The daytime temps have been in the low 70's and the frig has been steady at 40 degrees on #3 but the freezer is colder than before with the ice getting very hard. So just the one fan pulling air thru the back side of the frig really makes the frig work better.

I have a constant hot wire and inline fuse that I can use for the two fans when it gets really hot to plug the two fans into if the computer does not keep them running all the time.

I will report back when we get to SoCal this fall how it works with all three fans running with the temps 90-100 degrees.

It really helps to seal off the holes around the fans. The two fan pic is looking down from the top access/vent door. They are mounted mid way between the two access doors.

Thanks again Barney

Update!

With the temps in the 90's and the frig on 4 the frig temp has ranged from 36 to 38!

The factory fans have only come on when the temps are in the mid to upper 90's.

With the continuous fan running the temp has stayed at a steady 36 when the temps are in the 80's or lower.

[bigcitypopo]

Are there any other DIYers doing this mod. I found this...
http://www.snydersrvrefrigeration.com/page2.php

Looks trick...

[cmoecmoe]

Sorry for the delay. Got busy and have not been on the site in a while.

Yes, the last picture was shot down thru the chimney.

I bought the thermo switch from a local refrigeration supply store.

Down River Refrgeration - Detroit, MI

[Cummins12V98]

Irelands child wrote:
I 'abandoned' the rattling original fan in place as I could not reach the screws. I'll pull it off if I ever have to pull the reefer. I then Installed two ~45cfm computer case fans - should be enough vs that clunk that was in the fridge compartment, but since it was a 4 fan pack, have a couple more, just in case.

The original thermistor switch on the fridge cooling fins had died (these are generally cheap junk) so I ended up going to Home Depot and picking up an attic fan switch. Works perfectly.

This is what I used @$13.99USD with free shipping (also a one day $5.00 rebate on them as well):

http://www.newegg.com/Product/Product.aspx?Item=N82E16835103052

The 1 amp fuse is plenty of capacity for these two at something like .15 amps each.

Photo also shows the new 'attic fan' thermostat which is set at about 100*F.



I also have a bypass toggle switch just in case plus the wiring 'cleaned up' since the photo was taken.

Nice job!

The third fan I added is on a switch. I just let it run and the temps stay very constant. With the temps in the 60's to 80's the two factory fans have yet to come on. When I get to So Cal I am sure they all three will be working.

[Irelands_child]

I 'abandoned' the rattling original fan in place as I could not reach the screws. I'll pull it off if I ever have to pull the reefer. I then Installed two ~45cfm computer case fans - should be enough vs that clunk that was in the fridge compartment, but since it was a 4 fan pack, have a couple more, just in case.

The original thermistor switch on the fridge cooling fins had died (these are generally cheap junk) so I ended up going to Home Depot and picking up an attic fan switch. Works perfectly.

This is what I used @$13.99USD with free shipping (also a one day $5.00 rebate on them as well):

http://www.newegg.com/Product/Product.aspx?Item=N82E16835103052

The 1 amp fuse is plenty of capacity for these two at something like .15 amps each.

Photo also shows the new 'attic fan' thermostat which is set at about 100*F.



I also have a bypass toggle switch just in case plus the wiring 'cleaned up' since the photo was taken.

[austinjenna]

Can you tell me where you bought the thermostacically controlled switch from?

[Flanman55]

http://www.diytrade.com/china/pd/7132851/USB_mini_fan_yellow.html

This is what I added to the fridge compartment on my Torque. Made a heck of a difference. Just set it in there pointing up plugged into the the existing 110v plug in with a 3 way.

Added one in the Storage compartment for the 110v fridge I have in there too.


Hope that helps

[Wills6_4_Hemi]

slarsen wrote:
My refrig. tended in the mid-40's. A little scary. I got an inside portable refrig. fan from Tweety's that runs on two 'D' size batteries. Instructions said it would run for a month on the batteries. I doubted it, but in fact, it does.

Anyway, back to the topic: it reduced the temperature about 10 or more degrees, despite backing off one position on the temp. switch on the front of the refrigerator. And the temps are much more consistent, so no freezing things at the back while things in the door pockets are too warm. Like milk.

This might fix your problem, and for just under $20, you aren't risking much. Camping World has them, too, 'on sale' for about $16. Called a Frig Airator or some such.

I seen one of those while I was at MB a couple weeks ago and I almost bought it. My fridge stays cold enough but it is on the coldest setting. I am going to give them a second look. Thanks, Will

[austinjenna]

That is a great looking job. Where did you get the adjustable thermal snap switch from?

Also that last picture of yours, is that taken from on top of the rv looking down the fridge vent?

[Cummins12V98]

cmoecmoe.

That looks great. Similar to what came with mine from the factory only mine had two fans.

I sealed the air gaps around the fans with insulation and it helped with air cavitation.

[cmoecmoe]

Here is the mod that I did. I give credit to sc3283.

It really makes a difference. Ther refrigerator now gets down to 37-38 degrees. Seems to recover faster.

Fan was $15 from www.allelectronics.com/make-a-store/item/CF-400/12VDC-FOUR-FAN-ASSEMBLY/1.html

Attached to the fan frame is a adjustable thermal snap switch which is set to turn on at 100 degrees.

Used some aluminum bars and rubber feet I picked up a Home Depot.

Total cost around $40

[enblethen]

Across the top of the refer, it appears to have horizontal piece of wood. There is a straight tube there on the cooling unit.
Attach a curved paice of metal to the wood and roll it around to attach just above the vent access. There should be some type of support member there.
Check your PMs!

[Cummins12V98]

enblethen wrote:
I would leave the space between fans open. I doubt whether closing that up will help and it may even be detrimental.
In the first photo, I would get some metal and install curved piece between the wood member and the top of the opening. Make sure the metal goes between tubes and the cooling unit tubes. The squared off may slow the air down.
Looks good!

Thanks,

Not sure what you are talking about with the curved metal and wood comment?????

[enblethen]

I would leave the space between fans open. I doubt whether closing that up will help and it may even be detrimental.
In the first photo, I would get some metal and install curved piece between the wood member and the top of the opening. Make sure the metal goes between tubes and the cooling unit tubes. The squared off may slow the air down.
Looks good!