I hooked up a pair of 120mm high-tech, magnetic bearing computer fans in the rear of my fridge compartment to improve it's efficiency too. My camper came with a single Dometic fan in the back, which made too much noise when the thermostat cycled at night, waking me up occasionally. The new fans run at 1/2 the speed of my old stock fan, but are super quiet and actually move more CFM of air across the entire length of the upper cooling coil than the single, noisy factory unit. Together both new fans draw slightly less amps than the old, single, high-speed fan.

Here's a pic of the new set-up.



Chip

The fans used as standard equipment are quite noisy. The muffin tin type fans like shown in the photo are normally very quiet and would work every bit as good as the standard one, if not better. You can buy them from surplus electronics dealers like All Electronics | Electronic and Electro-Mechanical Parts and Supplies at Discount Prices for an average cost of $3. I would like to mount one that I have but I haven't come up with a thermostat to control it like the standard one has.

DW and I also find that our external refrigerator fan is a little loud when sleeping. Partly due to the fact that the bed is right next to the refrigerator.

This past weekend we camped at "Rock Island State Park" (post coming soon), and on the second night, around midnight, I turned the fan off. I don't know what woke me up but the little fan noise was making it hard for me to go back to sleep.

Is the thermostat for the fan part of the fan assembly? or is it a separate device that controls the fan? In other words, I wonder if we could replace the fan with a quieter one that doesn't have a thermostat with it IF the thermostat is a separate component.

Neal

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2001 Hi-Lo 22TL
2010 F150

That is my question also. I really don't want to remove the vent cover outside to look. Maybe Sam has that information. The muffin fans are noticeably quieter and I think they would be reliable. I think if the fan didn't run at such a high speed it would be much quieter.

We never run the fan at night or when we are boondocking because of noise and battery usage.

I found replacement Dometic fans listed on Ebay. They have the muffin fan, switch, thermostat and wire in the kit. I can't say that they are really worth $60 considering the cost of the separate parts.

Dometic Refrigerator Ventalator Fan Kit 3108705751 - eBay (item 390122905746 end time Apr-23-10 14:20:08 PDT)

I wish I could see what the temperature setting is on the thermostat because I found them on the Allied Electronics website. They have different fixed temperature settings.

I'm thinking that the existing fans could be made to run quieter if they had a cushioned or isolated mounting.

It took me a while to dig out my Dometic ventilator assy. manual (same part # as previously referenced.) The thermostat, called a fan limit switch, is Dometic part #3104723.006. It is set to come on when the compartment temperature reaches 100 degrees F. The manual doesn't state a shut-off temp. For the do-it-yourselfer, the thermostat is positioned alongside and to the right of the condenser coil (upper right hand corner of the back of the refrigerator.) The thermostat is set to interupt the red, power line which feeds the fan, and not the ground. According to Dometic, it should be fused with a 1 amp fuse between the manual fan switch (power supply) and the thermostat.

I agree, rubber isolating the fan would help, however the fan is inherently noisy. The solution I came up with was to replace the noisy (45db) plain bearing stock fan with 2, 23db artic cooling fans I got online from coolerguys.com. Though they are the same size as the stock unit (120mm), they only spin at 1500rpm compared to 3000rpm from the OEM fan. They are rated at 56cfm each, so the pair puts out 112cfm (compared to 88cfm for the single stock fan). Together they draw 0.3amps compared to .36amps for the single OEM fan. They are rubber mounted and use high-tech, fluid dynamic bearings that are ultra-quiet and good for a MTBF of 400,000hrs (20 times the rated life of the stock plain bearing fan).

I hope this helps,

Chip

Sushidog,

You have really been doing your homework. What was the item number for the fans? Did you use the OEM thermostat? I think that type of thermostat has one on/off temperature from what I have seen.

RichR,

My Dometic fridge had the cooling kit installed from the A-liner factory, so I just took out the noisy stock fan (which I now use as an exhaust fan above the stove in a bubble vent, sort of like a mini fantastic fan - waste not want not). Unfortunately, the cooler guys no longer sell that exact model of fan.

The closest thing I've found is this one: Fan It's the same brand with the same fluid dynamic bearings rated at 57 cfm, however it is PWM controlled for variable speeds. Just wire it to run at the 1500rpm speed for the same results. The extra bells and whistles make it a couple of bucks more, but at $9.95 it's still not too pricy.

A better choice might be this one: Fan w/ temp sensor Its also $9.95 with a built in temperature sensor so there's no need for a seperate thermostat. Instead of turning itself on and of it would just change speed gradually from 400-1300rpm from 32-38 degrees C (90-100 degrees F.) At 1300rpm it won't have quite the airflow as the model above, but dual fans should approximate the stock single fan's performance with much less noise and greater reliability.

Chip

I'm looking to instal a fan on my 94 funlite and came across this post. I have looked at many different ways of doing this but can't seem to decide. I like the idea of the fans with the built in sensor. Would you suggest 2 of them or just 1? Do these operate on 110 or 12 v? My camper is parked most of the time on land power so 110 is fine. Any suggestions are appreciated. I want to do this the best way not necessarily the cheapest.

Harry

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9421FLL
1996 Jeep Grand Cherokee (RIP old friend)
2004 Jeep Grand Cherokee 4.7L V8

The original fan in the trailer operates on 12V. Since sushidog didn't talk about reducing the voltage further (say to 5 Volts) I have to assume the new ones run on 12V too. I KNOW they are not 110V devices!

I think this is a mod I'm going to try once I get my trailer back from the RV doctor. Thanks, sushidog!

- Jack

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Hi-Lo 1707T
2005 F150 4x4 KR SCrew