Our freezer isn't freezing on the top part of the freezer. We found the condenser covered with ice when we took off the panel. My husband thought the door had been left partially open and this started the process. Anyway, we removed the items from the freezer and shut it off. The ice is gone from the condenser but the fan isn't running - even with the door button held down. How does the evaporator fan operate? Nothing is stated in the manual about it's operation. Whether it only comes on under certain conditions??? or if it should be running at all times that the compressor is running? I'm not asking for repair of the unit just information on how the evaporator fan operates?????? Help. Thank you. B A P