My refrigerator and freezer are not working well. Ice is melting and fridge not cold. Fan sounds off and on and freezer is getting too much ice on the back. Looks like it needs to be defrosted. I know heater is not working, but could it need new main board and defrost thermostat? Anyone that can help would be greatly appreciated.

Yolanda

Check the heater, but I would start with the thermostat test it for continuity when it's cold. If it has continuity then it's the heater, if it looks chared in the glass tube defrost the unit with a hair dryer or a steamer and order the part you need, that will get you working again until you can get the part in. If both of the above test good then the most expensive< the control board, must be replaced.
Nat