When temperatures drop, it’s normal for a heat pump to develop a layer of ice on the outdoor unit, sometimes several inches thick. This is part of how the system operates. A properly functioning heat pump will periodically enter a defrost cycle to melt most of the ice.
During the defrost cycle, you might hear a loud “whooshing” noise, see steam rising from the unit, and notice that the outdoor fan temporarily stops spinning. While this might sound or look unusual, it’s all part of the system working as designed. After a few minutes, most of the ice should melt. However, in extremely cold conditions (below 32°F), it’s not uncommon for some ice to remain. This is completely normal and not a cause for concern.
The key indicator of a healthy system is whether your home is staying warm. If it is, your heat pump is doing its job—even if the outdoor unit has some ice buildup.
If your home isn’t staying warm, you can switch to “emergency heat” as a backup. This setting can be found on your thermostat, usually where you adjust from heating to cooling. When selected, the outdoor unit will turn off, and the system will rely on the electric heat strips in the indoor air handler. Provided the heat strips are appropriately sized for your home, emergency heat should keep you comfortable.
As always, if you are having trouble with your system, we’re happy to perform an inspection and make recommendations. Give us a call at (252) 491-8637.
