We disagree with the door seal theory and the humid air theory. We installed this device
Found here and have never had another problem... No ice, and tons of air flow...
We had to laugh at a magazine article that suggested opening the door of our refer, snapping a pic, and slamming the door real fast. They said looking at the pic and never leaving the door open for more than 3 seconds would eliminate the ice... WRONG...
We hate to sound like a broken record. But why spend 60k on an RV and then not spend a few buck on something that helps you live in it? This is our home on the road, and I am certainly not going to snap a pic when I open the refer! Lol...