Why is My Heat Pump is Covered in Ice?

Below we have listed some common issues that could cause a heat pump to be covered in ice but additional issues could cause this problem

Issues with the Reversing Valve - Additional issues could be from a bad defrost timer, bad defrost thermostat or sensor, or bad defrost control board will prevent the heat pump from defrosting.

Defrost Control Issues - Even though your heat pump is completely iced up and you have to wait for the service professional, you can still have heat. Your heat pump’s thermostat has an emergency heat option that will turn on the backup heating unit (either electric heating coil or gas furnace) that will keep you warm until the system can be repaired.

What Can You Do For Get Heat While Waiting for the Service Professional - Heat pumps use the reversing valve to reverse the flow of refrigerant causing the refrigerant in the outside unit to heat up and melt away the ice. If during the defrost cycle the reversing valve sticks and can’t reverse the flow of refrigerant, it can’t melt the ice.