Loud refrigerator fan

[Spearfisherman7]

Anybody else have been annoyed enough by this to have replaced theirs with a quieter fan? Mine has a ADDA model AD0912UB-A71GP with a 34db rating and 70cfm volume.

[oakprk]

I just made a mod to the ducting on my Winnebago N8X installation and it significantly improved the gas cooling efficiency. It should reduce the fan run time but I haven't gone on a trip yet to verify it. The baffle, installed in the upper portion of the vent by Winnebago, was too far away from the condenser and a lot of cooling air was lost. I removed the screws on the sides of the baffle and remounted it closer to the condenser. The attached photos show the current configuration and where the original mounting holes were.

[SidecarFlip]

Your fridge will thank you with lower temps too. Mine actually shuts down entirely. I always thought that the flame in the boiler was always lit. Not so with my Dometic. It completely shuts down when it reaches the cold setting, then restarts itself when it needs to cool again.

The lights on the inside control panel stay illuminated but the burner shuts off outside which I thought was kind of neat. Not sure they all do that but mine does. Most of the time after the sun goes down which is fine with us. Even better sleeping.

[Spearfisherman7]

Second fan installed and it's so much quieter. You barely hear it now. Well worth $33!

[Spearfisherman7]

I ordered two noisblocker fans. Was planning on installing last night but as I was pulling on the cardboard packaging of the first fan, not understanding how it was packed, when it finally came loose, it slammed down on the concrete. Well I tested straight off the battery and it barely turned then I heard a pop and it was dead. The other one tested successfull and it seems noticeably quieter. Looking forward to not be annoyed by this on our next trip. The replacement fan is due to come in next week.

[SidecarFlip]

garyemunson wrote:
X2 on better fans. Generally, the fans are the cheapest thing the RV builder can find. Remember, the fan is not usually furnished by the fridge mfg. The fridges were originally designed to have an overhead vent (as they were designed before slides were developed). With the fridge mounted in a slide, now the venting has to be done with a second upper wall vent instead of the roof-mounted one. Obviously with this arrangement, the convective air flow is not as good so the fridge company just puts it in their instructions that side wall vent installs will require an add-on fan.

Actually, for restrictive side vent units, both Dometic and Norcold offer a builder installed fan option. It comes with a cheap, sleeve bearing fan (noisy) and a curved upper baffle (that is supposed to be installed but sometimes isn't) that directs the induced by the fan, airflow up, over the upper condenser and out the upper vent.

I replaced my one fan with a pair of Fluid Dynamic Bearing 120mm muffin fans wired into the existing snap disc rhermoswitch already installed on the upper condenser fin so on and off stays the same.

One thing you (or anyone) needs to look at closely, is the amount of insulation between the fridge body and the outer cabinet /enclosure. In my case the builder put very little insulation in. I added almost 1/2 of a roll of R12 unfaced insulation besides the fan and the builder in my case (Forest River) never installed the upper baffle to direct the airflow. Making a baffle was a simple matter of taking a piece of aluminum flashing, bending it to conform to the condenser and the outer wall and installing it with sheet metal screws attached to the inner frame behind the Filon skin. The baffle has to fit behind the condenser to the point where it blocks the airflow from getting into the cavity between the fridge body and the condenser itself. You don't want warm air (the upper condenser makes heat and it's that heat you want to expel) from getting into the upper cavity on top of the fridge, you want it to be exhausted through the upper vent.

I've never had to add internal fans in the fridge itself, it operates just fine. Remember to never block the inside fins (in the fridge) with food, to allow them to exchange cold with warm and, the freezer will always be colder (and cool down) before the fridge section will. That is how the unit operates.

[Spearfisherman7]

Thanks for the replies. I'm busy camping right now so when I get back to work I'll research fans on their time! I saw a couple models that where a variable speed with thermistor. They are 3 wire so not sure if that would work.

[garyemunson]

X2 on better fans. Generally, the fans are the cheapest thing the RV builder can find. Remember, the fan is not usually furnished by the fridge mfg. The fridges were originally designed to have an overhead vent (as they were designed before slides were developed). With the fridge mounted in a slide, now the venting has to be done with a second upper wall vent instead of the roof-mounted one. Obviously with this arrangement, the convective air flow is not as good so the fridge company just puts it in their instructions that side wall vent installs will require an add-on fan.

[SCClockDr]

Enermax Twister fan on Amazon. It sports a levitating magnetic bearing like the monorail. It floats on the magnetic field so the draw is low and it is quiet. I'm using 4 in our unit, 2 for the fridge, 1 to provide positive airflow across the batteries, & 1 to ventilate the Electrical bay. I prefer the 3 speed version.

[SidecarFlip]

Get on Flea Bay and enter in Fluid Dynamic Bearing Computer Fan and get one (or more) there. FDB fans are almost totally silent (except for the noise of the air in the blades). OEM's tend to use cheap sleeve bearing fans that make operating noise.