Refrigerator Fan

JimK-NY wrote:
Years ago I had a small refrigerator fan that ran off of 2 D cell batteries. I really could not see that it did much and was not worth the cost of frequently replacing the batteries.

philh wrote:
I bought one at a much lower price. It appeared to work, but I am going to wire in a computer fan to the light switch as suggested above.

Just got in via Amazon 2 computer fans, taped them together, ran 12V from a 12V socket and they did a great job keeping temps down compared to before.

I bought one at a much lower price. It appeared to work, but I am going to wire in a computer fan to the light switch as suggested above.

Years ago I had a small refrigerator fan that ran off of 2 D cell batteries. I really could not see that it did much and was not worth the cost of frequently replacing the batteries.

I like the Fridge Fan, but that thing looks huge! I have one of the little blue plastic fan like the one pictured. It works to circulate air in the fridge. I've thought about the ones that attach to the coils but so far just haven't done it.

I bought one just like the one in the OP's initial post, but it quit after a couple days. I bought another similar to it but without the on/off switch and it's still going strong after at least 5 years. Batteries usually last a couple seasons.

If you want a fan just to circulate the air inside get this one:Fridge Fan

It's much improved over the one you posted. It runs about a month on two D batteries and doesn't fall apart on first use.

If you want a fan to cool behind the fridge go with the recommendations that the other posters have suggested.

OK, this is how the RV refer works. You have the Evap fins. The air must flow up from bottom thru the fins to remove the heat. So, ANYTHING that helps move that air is a good thing. BUT, moving the air too FAST will not remove the heat correctly. The air flows from convection. Hot air rises. That is why it is important to NEVER block the back wall of the refer with items that will stop the flow of this air, Plastic bags and such are a no-no against the back wall. Those fans can help as long as they are installed at the lowest point and BELOW the Evap fins. DO NOT install in correct place and they are useless. Doug

I have a 1.8 cubic foot 12vDC compressor fridge.

I put a small low cfm, low amp draw 40MM computer fan inside of it.

With the fan disconnected I need a setting of 4( of 7) to maintain sub 41F everywhere in the fridge, and the floor will be 27f or well below depending on the time of the previous door opening and the contents.

With the fan on I use a setting of 2.2 to maintain 32.5f +/- 1.5f everywhere inside the fridge.

The fan does add a small heat load to the fridge which then must be removed which is why I searched the lowest amp draw fan I could find. The internal fan will not make it use less power overall, but it will even out the internal temperatures greatly, and will help cool down warm items placed withing much faster, something compressor fridges do many times better than absorption fridges to begin with.

As far as condenser ventilation, on exterior of fridge, this is also very important, and my condenser, which was designed to have a 120MM computer fan mounted to it, is bathed in the coolest possible ambient air that has no chance of being recycled across the condenser as the
filtered air, pulled from the floor, is pushed through the condenser, across conpressor and compressor controller and out of the vehicle. or in winter into an adjacent compartment.

I've No issues maintaining 32.5f or less no matter the ambinet temps, and I still have more than half the dial to turn if I want it colder.

I wired my 40mmx20mm 12v interior fan to the interior light before the magnetic reed switch. It is a discontinued Sunon Maglev rated at ~6.2 CFM and 0.03 amps, and I leave it running continuously and it has been doing so since October 2012.

I'd use a larger internal fan if I had a larger fridge, but there is no need to go nutty on the CFM rating.
The Noctua NF-F12 is 120Mm x 25mm fan and moves 53CFM for 0.05 amps of draw, and is very good at pushing air through restrictions, like the fins on an absorption fridge, but that much CFM is likely overkill for an 8 cubic foot fridge.

The most expensive 12v computer fan is in the 25$ range, and they come in many many sizes, from 25mm to 230MM, they also come in 5v and 24v versions, but the options are less numerous.

If you don't want to tap into any internal wiring you could hook a 5v fan to 2 D size batteries in series for ~3.2v. Since fans draw so little juice you can also run 26 gauge wires through the door seal.

I don't know just how effective internal air circulation is inside Absorption fridges, but I do know it keeps ice from clogging the fins directly in the path of the fan's flow, and it works great in my compressor fridge to cool down items placed within faster, and keep an even temperature across the whole interior, and I'd not willingly disconnect it no matter what.

Acampingwewillgo wrote:
30 bucks....are they out of their mind! I had one many years ago...didn't seem to do much. Placing a whisper (computer Fan) wired to a switch would probably work better.

did that too. same result. only thing that worked was a muffin (computer) fan wired to a thermostat and mounted in the chimney.

30 bucks....are they out of their mind! I had one many years ago...didn't seem to do much. Placing a whisper (computer Fan) wired to a switch would probably work better.

clicky

had one. found it useless. might still have it in a junk drawer. if i do you can have it.