Why Is My Heat Pump Freezing Up?

Outdoor HVAC Units

Running your heat pump through the moderately cold winters in Virginia Beach, VA saves you heating costs. That’s unless your HVAC system is constantly freezing up, which keeps you cold and drives up your energy costs. Consider some of the reasons why your heat pump freezes up and what you can do about it.

Insufficient Refrigerant

Your heat pump relies on refrigerant to absorb heat from outside and transfer it to the air inside your home. To do this, it must have the appropriate amount of refrigerant. When there is too little, the coil gets too cold and freezes over.

Restricted Airflow

In addition to the refrigerant, your HVAC system also depends on sufficient airflow to distribute the warm air. Insufficient airflow on the low-pressure side of the system allows the refrigerant to get too cold, leading to freezes.

Airflow restrictions commonly happen when you neglect the air filter. It can also happen when you have a faulty circulating fan, dirty fan blades or clogged coil fins. Routine heat pump maintenance is the best way to clean your system and reduce airflow restrictions.

Mechanical Failures

Besides the circulating fan, your HVAC system may experience other mechanical failures that cause freezing. The first is a faulty defrost control board, which tells the unit when to defrost the refrigerant coils.

The second is a faulty reversing valve, which can get stuck in the heating mode position. This prevents it from pushing warm refrigerant into the outside heat pump unit to defrost it. While reversing valves do fail, tests conducted during a routine HVAC system maintenance visit will often spot them.

Don’t let a freezing HVAC system keep your home from warming up to your desired temperature. Our family-owned business has been serving Virginia Beach since 1953. Call to schedule your heat pump repair services with our award-winning technicians at Climatemakers.