Chris S Highland , CA February 15, 2016 Appliance: Frigidaire Refrigerator FGHB2869LF8 Frigidaire Refrigerator Fghb2869lf8 / : Ice maker evaporator would not defrost causing a large build up of ice in the evaporator housing. How to replace Defrost Heater. Replaced evaporator heater and housing. Just make sure you also replace the thermostat. If not it is a little challenging to get the wires out of the old thermostat/ heater plug into the new plug. Also if you have the same problem be prepared to have a good heat gun to melt the ice buildup around the evaporator and drain hole. The ice build up was so bad that it destroyed the evaporator cover and was leaking into the refrigerator or should I say ice was forming below the evaporator cover into the refrigerator. 31 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 1-2 hours