Why Is My Heat Pump Freezing Up?

Our team at Wm Price Heating Co regularly gets calls about frozen heat pumps. Though common, a heat pump freeze-up usually means your system’s components are not working correctly. Freeze-ups on heat pumps can happen both in heating and cooling modes. During the cooling operation the freeze-up will happen on the indoor unit and in heating season the freeze-up will happen on the outdoor unit. Both are complex issues that differ, but often the issues that can cause a freeze-up are similar. Sometimes, you can fix it yourself. But oftentimes, you will need to call a heating, ventilation, and air conditioning (HVAC) professional like us, as the problem may require a part replacement or complex repair.

Heat Pump Brain Freeze

To help sort things out, here are the six usual suspects causing heat pumps to freeze up:

1. Clogged Air Filter

When air filters are left to collect particles for too long, they become clogged. This hinders airflow, which can not only cause an issue with the indoor unit but can affect the outdoor unit’s operation. Dust, pet dander, and smoke are just a few examples of things that can clog your filter.

The National Air Filter Association (NAFA) recommends changing your system’s filter as soon as it is loaded with dust and debris. How quickly your filter becomes clogged depends on many factors in your home. At Wm Price Heating Co, we recommend switching to a new filter every three months depending on which type of filter you use. Please reach out to Wm Price Heating Co for any help with filter replacement questions.

If replacing your air filter, turn the system off, allow the ice to defrost, replace the filter, and turn your system back on to resume operation. If this does not correct the problem, contact one of our trained experts to come out to help, it may be time for routine maintenance.

2. Low or Empty Refrigerant

If your heat pump is low on refrigerant, there may be a leak. This can be from of fatigued metal in the coil or line set. Also, components can rub against the refrigerant piping over time, it could eventually puncture it, leading to a refrigerant leak and possibly a freeze-up on the outdoor unit in heating or a freeze-up on the indoor coil during cooling. Even worse, it may lead to total loss of refrigerant charge.

When the pipes start to show ice or you see water dripping from the indoor unit, turn your heat pump off and contact one of our HVAC professionals for immediate inspection.

3. Filthy Indoor Coil

Refrigerant flows through your heat pump’s indoor coil. It transports heat into your Warren home during heat mode and removes it during cooling mode. When the coil becomes dirty, its ability to transfer heat is impaired and may not allow enough air to flow through it. Compromised airflow can lead to inefficient operation in both heating and cooling modes, compressor damage, noisy operation, along with a freeze-up in cooling mode.

If you notice any of these symptoms, turn your heat pump off. Allow the ice on the indoor coil to melt before turning your heat pump system back on. If your coils freeze back up, call one of our HVAC team members as it may be time for routine maintenance.

4. Faulty Blower Motor

If your blower motor on the indoor unit is not up to speed, it can wreak havoc on your system, leading to several problems and possibly a complete breakdown.

The blower may start and stop intermittently, run at a reduced spinning cycle, or not run at all. If this is the case, have someone from Wm Price Heating Co inspect the system for the cause.

5. Faulty Outdoor Fan Motor

Much like when the indoor blower motor is not operating, an improperly operating outdoor fan motor can wreak havoc on your heat pump systems operation. During heating mode operation this could cause the outdoor coil to freeze and reduce the ability to provide enough heat. During cooling this could cause damage to the compressor, inefficient operation, reduced cooling capacity, or a complete breakdown.

If this is the case, have someone from Wm Price Heating Co inspect the system for the cause.

6. Filthy Outdoor Coil

Refrigerant flows through your heat pump’s outdoor coil which transfers heat into your Warren during heating and from your city home during cooling mode operation. It transports heat into your Warren home during heat mode operation and removes it during cooling mode operation. When the coil becomes dirty, its ability to transfer heat is impaired and may not allow enough air to flow through it. Compromised airflow can lead to inefficient operation in both heating and cooling modes, compressor damage, noisy operation, along with a freeze-up in heating mode.

If you notice any of these symptoms, turn your heat pump off. Allow the ice on the outdoor coil to melt before turning your heat pump system back on. If your coil freezes back up, it may be time for routine maintenance. Call one of our HVAC team members.

7. Inefficient Equipment

Depending on your heat pump model and your Ohio home’s geographic location, some air-source heat pumps (ASHPs) do not always operate as efficiently as when the system was new. As systems age, loss of efficiency will occur over time due to wear and tear. Lack of maintenance will also cause a loss of efficiency.

Also, the unit should be level with the ground and above the snow line; any tilting can cause moisture to get trapped, and unable to drain during defrost become frozen.

Finally, your unit should be away from obstructions such as exhaust vents, shrubs, and overhangs that can allow moisture to drip into the unit that can cause ice formation. Likewise, anything that can affect airflow through the coil should be kept away from the outdoor unit. Remember, the outdoor unit is made to withstand all weather conditions so the unit should not be covered or enclosed. During the winter, always check for ice or snow accumulation around or on your unit and clear it to prevent further issues.

Contact Us With Any Heat Pump Issues

Experiencing a frozen heat pump or any other issue? Our Wm Price Heating Co. team of experienced HVAC professionals is just around the corner in Warren, OH, to assist you. Call us today at 330.545.3722 or request service online if you are experiencing any issues, if it is time for routine maintenance, or you would like to explore options of a more efficient heat pump system.