Main problem.


Ice forms at the inlet of the styrofoam duct that leads from freezer compartmrnt into the refrigerator section. This area is covered by a plastic cover that has some frost/ice in it. The stuff in the styrofoam duct is definitely hard ice, not frost. It took me about 15 minutes with a hair dryer to melt the ice in the duct. After I melt the ice, the unit will work for several weeks, but then the ice builds up again. There is also some ice on the refrigerator wall near the crisper - the side next to the freezer.

There is no ice on the coils in the freezer and the freezer is working OK. Fan is running OK

What should I check? What is the most likely cause?