Michael M Fort Myers , FL September 15, 2018 Appliance: Maytag Refrigerator MSD2454FRW Maytag Refrigerator Msd2454frw: Coil frozen over. How to replace Refrigerator Defrost Heater And Thermostat Assembly. Replaced the heater & therm assembly unit Do-It-Yourself Rating: Repair Time Estimate: Less than 15 minutes