1 week ago we noticed that the top of the freezer was warm but bottom was frozen. Noticing ice at the bottom and after reading the posts here, I determined the evaporator fan was not working. REplaced fan and freezer cooled normally. Yesterday same thing - saw the fan working but evaporator coils completely iced over. Checked and thermostat has continuity (<10 ohms) immediately upon unplugging freezer. Heater also appears to have continuity (~15 ohms?). Can't feel any heat on the heater at the bottom when the freezer is plugged in (not sure if I should or not). Coils already "frosted over" from last night. Freezer working but concerned as we are to leave for vacation for a week tomorrow.