Why Does My Heat Pump Have Ice On It?

The truth is—it’s normal for the heat pump coils to be covered in white frost in the cold season. But what’s not normal is for your entire heat pump to be encased in ice for an extended time.

Ice on heat pump could indicate a problem—and the first step toward preventing and solving the problem is knowing what causes it. Here are possible reasons:

Faulty Defrost Functions

Heat pumps feature a defrost mode that allows the ice to melt off on its own. But when something’s wrong with the defrost functions, your system won’t complete the defrost cycle, causing it to freeze up. With this, you need to check the controller, relay, reversing valve, thermostat, and the sensor. Any of these components might need some adjustments or repairs to activate the defrost mode. Be ready to call in a technician to help you with how to defrost a heat pump properly.

Low Refrigerant Charge

When your heat pump runs low on refrigerant and isn’t getting warm enough, it will frost over quickly under high relative humidity. In this case, your technician should repair the leak or add refrigerant to the heat pump outside unit. If done inappropriately, it may lead to serious heat pump compressor problems. Be sure to keep the right refrigerant level of your system to avoid this scenario this winter.

Airflow Issues

The ice on outdoor heat pump unit is probably caused by airflow issues.  Proper airflow is an important aspect of a heat pump to pull in the heat from the outside. But when the flow of air is restricted, the heat won’t pass over the evaporator coils sufficiently—conducive enough for the system to ice up. This is why you have to clear your heat pump from any blockages in all directions to prevent this bad scenario.

A frozen heat pump is never considered normal under any circumstances. There’s always an external or internal issue behind it—like those mentioned above. As with any heat pump malfunctions, it’s best to call in an expert to handle the problem appropriately.

For more information about your heat pump issues, feel free to contact us at NAPPS Heating, Cooling & Plumbing. We offer free in-home consultation, plus quality and affordable residential and commercial HVAC services in Longview, TX and surrounding areas.