One very common question asked by first-time swimming pool heat pump owners particularly by those living in colder climates is: Why is my unit covered in ice? Having serviced heat pumps for over 30 years, we at AquaCal know not only what causes this ice formation, but also how to prevent it from damaging your unit.
How Ice Forms on a Heat Pump
In order to explain how ice forms on a heat pump, we first need to clarify two points of a heat pumps operation:
- When a heat pump operates, its evaporator coil constantly rises and drops in temperature as the refrigerant inside it collects and releases heat. When it falls in temperature, condensate water forms on it. In fact, a heat pump typically produces about one gallon of condensate water per hour of operation.
- When air flows through a heat pump, it passes over the evaporator coil and drops in temperature by 9° to 18°F (5° to 10°C) as its heat is collected by the evaporator coils refrigerant.
So, when air below 50°F (10°C) passes through your heat pump, it can cool to below 32°F (0°C) and freeze the condensate water on the evaporator coil.
How to Prevent Ice from Damaging Your Heat Pump
Ice buildup can block airflow to your heat pump, which can result in damage to its internal components. You should therefore take all steps necessary to prevent ice from collecting on your heat pump.
Many heat pumps are designed to automatically shut off when the air temperature falls below 50°F (10°C) and to start again when the air temperature rises back above 50°F (10°C). Some heat pumps, like AquaCals IceBreaker, have defrosting systems that automatically activate when the units become disabled by ice. Some heat pumps, however, are not equipped with an automatic shut off or defrost feature. These heat pumps need to be manually disabled.
Furthermore, heat pumps are most likely to develop ice during the coldest parts of the day. You should therefore avoid running your heat pump late at night and early in the morning, especially during winter months.
Hopefully this article helps you better understand your heat pump. If you still feel uncomfortable about the ice covering your heat pump, you can always contact a licensed heat pump professional. Feel free to leave any questions or comments below!