Heat pumps operate differently from gas furnaces, so the air coming from the vents may feel less intensely hot even when the system is heating normally. During cold, damp weather, frost can also develop on the outdoor coil and the system may temporarily enter a defrost cycle to remove it. This is normal, but heavy ice that does not clear, frequent cycling, or a home that will not stay warm may indicate a problem. Apollo Heating and AC can inspect the system and provide heat pump repair or maintenance when needed.