Interior Frig Fans

CJW8 wrote:
Observation and comment:
No interior fan is going to make a fridge cooler.

Well, shades of grey. If the goal is to cool everything down faster and keep internal temps more even, then the internal fan is making the overall fridge interior colder, faster. Especially if a compressor fridge which work much faster than absorption.

We had 100F ambients here yesterday. I was emptying ice trays into a ziplock, and refilling them, every 45 minutes and keeping sub 38f box temps. I love my danfoss powered compressor fridge.

I could improve insulation on door for further increase in performance, but it is not required.

We had the pictured type of fan in our previous 5th wheel and now in our TC. I have a wireless temp monitor in the fridge. Yes, they do help the cooling temp by about 3-5 degrees lower. Also excellent for distributing the cold air throughout the interior of your fridge. If you buy one, get the option for a fan grill which will keep items from being pushed into the fan blades and breaking them.

Observation and comment:
No interior fan is going to make a fridge cooler. It is going to cool to the thermostat setting, fan or no fan. It may, provided there is enough free air space, circulate the air so there is more even cooling. This allows landyacht's beer cool down faster.
I don't see how having fans that only blow across less than one third of the cooling fins would be of much value. I would think a fan that circulates air in the overall box would provide more even cooling or have a fan that blows across ALL of the cooling fins.

I snapped mine in the grill wires on the bottom shelf with the fans hanging under the shelf.

It has been so long that I don't remember how I tapped in but mine is powered off of the wiring to the interior light. When you hit the on button for the frige the fan comes on and goes 24/7

We have the little white fan that uses 2 D cell batteries. With the fridge well stocked some eggs on the top shelf froze and the drinks on the bottom shelf were too warm. Stuck the little fan in the back corner of the bottom shelf and it did the job. Even temp top to bottom even when the fridge was pretty well stuffed. The 12v type would be nice. I bought the cheap battery one while on the road for a month.

We've had a chance to use this interior frig fan we purchased off eBay for almost two months now.

Installation:

Didn't have access to any 12vdc source inside the frig (interior light turns off when the door is closed). Fortunately the wire on the frig fan was long and thin. Fed the wire through the inside of the water drain tube (located on the bottom of the water collection tray located below the interior aluminum fin assembly). The drain tube exits on the rear of the frig (accessed on the outside of the rig). From there it was only about 18" to the nearest 12vdc source. The frig fan came with an inline fuse already installed. The water in the water collection tray continues to drain normally.

The frig fan has two friction clamps that are used to mount/hang the entire interior frig fan assembly onto the aluminum fin assembly inside the frig. Had to bend the two friction clamps open quite a bit to get it to slide over the frig's aluminum fin assembly. Got to be careful not to try and force these clamps onto the aluminum fin assembly. It doesn't take much force to break these aluminum fins loose from the main assembly.

Operation:

We purchased the frig fan with the toggle switch option, but we've elected to leave it on 24/7. The frig seemed to cool down from ambient temps to operational temps much quicker. I'm guessing 6-8 hours vs. 9-12. It also seems to recover more quickly during daily use. The most dramatic change has been the reduction in frost on the aluminum fins on the interior. In AZ we had no problems with frost due to the low humidity, with or without the fan. However, in FL where the humidity is much, much higher, frost would typically build-up 1/4 - 1/2" thick on the interior aluminum fins without the fan. With the fan, there is typically no frost on the fins directly behind the interior fan and a minimal amount to the left and right of the fan.

Sound:

With everything in the rig turned off you can hear the fan operating if you make a point of listening for it. Otherwise, it's not noticeable.

Current draw:

375ma. A bit on the high side due to the two fans. To reduce current drain I'm guessing one could disconnect one of the fans and not lose a lot of functionality.

Overall Assessment:

For $18 very pleased how this interior frig fan has improved the operation of our frig.

I've been using a 40Mm sunon Maglev fan in my 1.8 cubic foot 12v compressor fridge. It draws only 0.03amps, moves only 6.3cfm

It greatly speeds cooling of warm items placed within, and evens out internal temps all to within 1.5 degrees of each other, whereas without there can be a 15 degree spread from warmest spot to coolest.

With such a low amp draw, I just let it run 24/7, and in October this year, it will be running continuously for 4 years. I took power for it from the LED light.

The fan motor generates some degree of heat which then must be removed, so overall the fan can't help the fridge use less power, but I have power to spare. When I put warm beer inside of it I want it cold ASAP, and this internal fan makes a huge difference in the time it takes to make warm cheap american beer drinkable.

Absorption fridges cool so much slower I've no idea how well internal fans would work in them, but I certainly would not buy fan marketed for a fridge, but search out a low CFM low amp draw dual ball bearing computer fan or a hydrodynamic bearing fan and make my own mounting method.

These fans can vary extremely widely in amp draw for air moved and noise made.

Not much CFM is needed for inside the fridge and the slower and lower the amp draw, the less heat will be introduced into the fridge.

Thanks for everybody's responses. Looks like this interior fan is a hit or miss. Some like 'em, some don't.

Again, our frig works well. It came from the factory with a chimney fan that's thermostatically controlled, plus the top vent is on the roof (vs. a less efficient side vent). Was able to sustain 40 degrees in 112 degree heat. Up to about 100 degrees it kept temps around 32-34 degrees degrees.

The frig on our previous toy hauler had a difficult time staying below 40 degrees when ambient temps got above 85-90. Discovered the factory didn't install the rear baffle correctly. Had to move it 2-3 inches closer. That helped. What really go it working well was the installation of two computer fans near the upper coils (in the chimney area).

Anyhow, we'll probably give this interior fan on eBay a try. We're ok with taking a $15 gamble. Would be nice if we can improve our frig's performance in extreme temps.

To me it seems like where you camp is a bigger factor. I hear people say all the time how well there refrig works, but they don't say they are camping where it never gets above 80 degrees. Probably no need for a fan in those temps. When you live where I do and summer temps are over 105 then no my refrig doesn't work worth a darn. Those fans help alot! Sure, correct venting is a big issue for many installations but the temps the refrig is working in is a bigger factor. I have every device known to man to keep ours cool during the summer and I still bring an ice chest for when the temps get to a dangerous level. I have the same thermometer as pictured earlier. Do the fans work? yes.. does a fan in the stack help? yes! Everyone's situation is different.

I just ordered on yesterday but the one with the grill on the front. will let you know once I get it and use it for a while.