Kenmore freezer section of side by side stops freezing for a day and then will start working fine again. Removed cover from the inside and the fins/coils had a frost of thin ice on them, now that it has stopped freezing it has a 1/8 inch or so layer of ice on them. Could it be the defrost timer, or what? I do not want to buy a new freezer. Its 10 years old.

Sharon, October 2011