Dometic ventilation fins freeze

[artrosch]

We've got a Dometic Royale fridge in our Newmar Mt. Aire. It works well, but has a chronic tendency to freeze the ventilation fins. Do I have that terminology right? I mean the fins on the top shelf of the fridge section. We keep small items on that shelf, like yogurt and butter. We run the fridge at number 3, almost always on AC as we fulltime at a campground. It seems as if it needs defrosting every couple of weeks. That doesn't seem normal.

Any help?

Thanks
Art

Author of AVOIDING THE POTHOLES:ROAD STORIES IN A CHANGING AMERICA
blog: The Blog Of Fascination

[Ray,IN]

The most common culprit is the door gasket. Using a dollar bill, close the door on the bill at several places and try to pull it out. If it comes out easily the gasket is leaking, and should be cleaned thoroughly, if the bill resists pulling out, that section of gasket is good. If it does not pass the bill test after cleaning, replacement is the 2nd solution.
Many folks use a small battery-powered fan inside to move air around, which reduces condensation, and distributes cool more evenly.
The thermistor, located on one of the cooling fins, may be moved down 1/4" to raise the temperature a bit. Allow 24 hours for the frig to adjust completely. This should allow the ice/frost to melt a little and drop into the catch pan below it and drain away.

[justimagination]

Don't forget to check your humidity switch @ the top of the fridge above the freezer door, make sure it is on. Good luck.
David G.

[62Morgan]

The "humidity" control button is probably turned "off. It's called by another name I believe.

[Norm4015]

Quote:

Originally Posted by 62Morgan The "humidity" control button is probably turned "off. It's called by another name I believe.

The humidity control is named Climate Control and it turns on a 12 volt heater around the door gaskets to dry up humidity. Some Dometic refrigerators have that feature and some don't.

I have found if I keep the temperature set to number 4 the refrigerator will stay about 34-36 degrees and the fins will freeze over in 2-3 weeks. But if I set the temperature to number 3 the fridge stays about 38 degrees and the fins never get any frost or ice.

[artrosch]

Thanks. Our gasket doesn't hold money, that's for sure. We do have a humidity switch above the freezer, and it's been "On". I'll try moving the thermistor (is that a white sliding object at far right?). And we'll clean the gasket. I like the batter operated fan idea. This has been very helpul.

Art

[TXiceman]

It is normal for the fins in the frig to have some frost on them. But do check the door gasket for tightness and make sure the door is fully closed.

Ken

[Ray,IN]

Yes Art the white sliding object is the thermisiter. Look at the frig PC board, top left corner. It might have a thermister adjustment pot, some do, most do not. On your door gaskets, before replacing it, try heating it with a hair dryer and re-forming it (pull it away from the door), this might work to make it seal better, but eventually it must be replaced.

[Gary RVRoamer]

Frost on the fins comes from moisture in the air, and air gets into the fridge whenever you open the door or if the door gasket is leaky. Folks who tend to have the door open a lot (e.g. trying to decide what item to get out) have more frost problems than those who do not. And a leaky door seal constantly lets in warm, moist air.

The climate control switch won't affect frost on the fins - it is for condensation around the edges of the door. But if you turn the Climate Control off and see a lot of water build-up around the door, that's another sign of a leaky door gasket.

Moving the thermistor on the fins changes the temperature, biasing it either up or down. You can make it warmer inside the box and reduce frost that way, but you probably don't want it warmer inside. You could achieve the same thing by changing the temp control.