RV Refridgerator Fans

We are new to camping and we just bought a new 17' Casita Travel Trailer.I read someplace that you can lower the temp of your fridge by 40% if you install a fan.The fridge in our Casita is 4.0 cu ft. Can someone tell me where can I buy the fan, what kind is best to buy solar power or 110 volt, where does it get installed and last where can I get step by step instructions pictures if possible on how to install it. Wow!! I'm not asking for much am I... Ha! Ha!
New Camper
Bill McCarty

There are two kinds of fridge fans that I know about. 1) Internal (within the fridge itself). Intended to circulate the air inside the fridge to help maintain a uniform temperature throughout. (Camping World #6675 "Fridge-Mate" fan. Self powered, runs on two D-cells). 2) External, mounts in the fridge vent. 12 Volt, thermostatically controlled fan to assure circulation over the condenser coils to improve cooling efficiency during hot weather.
Larry A.

I use two of the small battery operated fans. They use two "D" batteries and will run for days on end. They do help circulate the air and keep food, that migh otherwise be the farthest from the cold, to stay cold. I can't say if it makes the frig any colder (never ran the frig yet without a fan the frig and freezer sections. They are cheap and need no electrical connections.
Rob


I too use the battery powered Fridge-Mate. Last time out I forgot to load the batteries in it and could really tell the difference in the way the fridge cooled. There were hot spots. I plan on installing one of the coil fans sometime in the future just to help out the fridge somemore.
Rob
Steve


I use 1 battery powered Fridge-Mate that sits on the shelf in the back where it blows over the cooling fins. It does cool quickly. I had it almost from the begining so I can't judge how effective it is. Don't think I need the outside fan since it maintained cold temps in the 100degree NM desert. I keep an indoor/outdoor thermometer in the fridge, outdoor is the freezer, indoor is fridge. If I can't read it, the fridge is well below freezing. Could also use 2, mounted over the fridge, 1 probe in the freezer, and the other in the fridge and route the wires out of the way through the door.

My fridge manual recommends adding a baffle at the top if none is added now and shows a simple diagram in the manual. This is to encourage natural airflow, heat rises and pulls cold air in the bottom. Also, make sure you have no birds nests inside.

Rob, I've considered using a 12V PC fan that are under $10 and come in various sizes vs the RV version costing 3-5 times as much. I wanted to at least camp in it once in the summer and see before I pulled more wire. I would have to fabricate my own brackets such as the hardware store right angle mending plates.

Mickey


Here is an idea I've used and has worked well for me. Oh, I'm talking about using one of the small (3") PC fans.

Under the frig vent cover the opening is covered with a screen to keep out the bigger creepy crawlys. On my rig the screen had been partially removed for access and then reattached. I mounted the fan on the underside of the screen using small tie-wraps. No rattles on brackets, simple as can be. For wiring I use 2-cond bell wiring as it is small but adequate for the job. I attached to fan and dropped wire down through the various fins and plumbing to reach the bottom of the frig. I spliced this wire into the wire for the controller so that fan got power only when frig was turned on. I also inserted a small 2-position switch in-line so I could turn the fan off even when frig was on. Did this so the fan could be off during cool weather use. Has worked great for several seasons.

I Did about the same thing for an interior frig fan, use a small CPU fan with heatsink. Mounted to back wall of frig with 2-way foam tape. Again use small wiring and feed wiring out of frig by running wire through drain hose for water catch tank located below the cooling fins. Hooked as I had done for other fan so like the other fan, only works when frig is turned on.

Hope this give you something to think about.

For all. After mounting my exterior fan I made some temp readings. Air, right above the fan was 20°F warmer than air off center and away from fan. Amb temp was in mid-90's and air above fan was about 119°F.
Good luck.
Rob


More great ideas! I love tinkering with my rig so this will be added to the "to do" list. The fridge vent fans run around $30.00, so this will save a chunk of change. Thanks for the idea. This forum has saved me so much trial and error by providing first hand "it worked for me" information. It's great!
Thanks,
Rob
Steve

I use two fans on mine.. one inside the box and one outside. For the outside one, I use a 120V muffin fan mounted on brackets above the coils (blowing up) and just below (and inside) the roof vent. This fan is reated for 100CFM. I wire this in parallel with the heater wires for the 'fridg. In that way, it only comes on when I am on electric and when the 'fridg is asking for cooling.

For the inside fan, I use a small 12 volt fan for a computer. I wire it ACROSS the interior lamp SWITCH. In that manner, it comes on only when the door is closed and the lamp is off. These fans have made a MAJOR difference in the way the box performs.

I have suggested this to many people and all have been very satisfied with the results. Both fans are available at computer supply stores and cost in the $5.00 range.

Good luck and happy camping!

Steve
Harold G.


My 5th wh came with a 12v fan already installed at the top of the vent where the coils are. I wanted more air flow so I mounted another 12v fan (from Target and/or Walmart)at the bottom of the vent. I cut off the cigerette adapter end and spliced the cut wires into a 12v source behind the refrig. So I have a fan pushing and one pulling the air flow. Worked so good that I could lower the thermostat one notch. At nite time I turn off one of the fans. Needed it in this 100+ temp of So Calif.
Les Doll


Thanks all for the comments:

Just to clarify a few things about the RV absorption refrigerator -

The heat source, meaning the propane flame or the electrical heating element, is used to "elevate" the amonia/water mixture to the top of the cooling unit. There after it is gravity and the PHYSICAL change of state of the chemicals that does the rest of the cooling work.

The air flow across the back of the refrigerator is also gravity controlled - hot air rises and flows out the roof vent. Cooler air is drawn in through the bottom or side vent to replace this rising air. This rising air collects heat from the evaporator fins as it passes by, thus removing heat from the cooling unit.

Any assistance, especially in HOT weather, will help with this heat dissipation. A fan to move the air need not be a large one to effect a higher efficiency. Also, the addition of sheet metal baffles to direct the moving air through the evaporator fins can be very effective.

Use a mirror to look up into the back of the refrigerator compartment. There should be a maximum of one inch clearance between the evaporator coils and the facing wall. If the clearance is more than this then your refrigerator will benefit by the addition of baffles. It may be necessary to remove the refrigerator to install the baffles, but that is not a hard task to do and may result in a very much improved cooling efficiency.

Les Doll
RVerscorner.com

This sounds like an easy project, other than where exactly to wire in the fans... I have a norcold 8310 EG3, and wonder if anyone has a wiring diagram and knows where to splice in the fans...? Thanks