Trane Heat Pump: 4TWB, 2TWR, 4TWR Re: Defrost Problem / Frozen Outdoor Coil The outdoor unit becomes completely covered in thick, white ice. Qty Possible Causes: Bad Coil Sensor 1 Mis-Located Coil Sensor Inoperative Condenser Fan Motor Bad Defrost...

Trane Heat Pump Re: Compressor Won't Run / Compressor Can't Start With a heat pump system, as long as the auxiliary heaters are working, the conditioned space should stay at or near the thermostat heating setpoint, but if the heat pump itself is not working the customer may report one or both...