The technology of heat pumps has advanced significantly during the last decade, and new models are capable of handling more intense cold weather than earlier ones. As long as a heat pump is properly sized and matched to home and receives a professional installation, it should be able to provide a family with the heat they need until it turns over to the cooling mode in the spring.
Heat pumps may start to develop frost along their outside units during the winter. If you notice this occurring with your heat pump, you’ll probably wonder if it’s a malfunction and whether you should call for repairs or not. We’ll take a look at what ice on a heat pump means:
Why ice might appear on a heat pump
For the most part, the appearance of frost on the outside unit of a heat pump is a normal part of its winter operation. When in heating mode, the outdoor coils absorb heat from the air, but also condense moisture at the same time. This moisture settles along the coil, where it will turn to ice if the temperature is below freezing and humidity is higher 70%. Although the presence of ice will restrict the coils’ ability to absorb heat from the air, the heat pump is designed to deal with the situation. Defrost controls built into the system periodically reverse the direction of refrigerant through the coils to release heat through them, which melts off the ice.
However, the defrost control can malfunction, as can the reversing valve that changes the direction that the refrigerant moves. If either of these occurs, the frost won’t melt off and will continue to build up. If the heat pump has refrigerant leaks, it will also restrict the defrosting cycle from successfully melting away ice. Refrigerant leaks are serious problems and must be dealt with as soon as possible before they cause damage to the compressor.
If you see frost on your heat pump that doesn’t melt off after two hours, then you may have an issue. Contact HVAC repair technicians right away.