If you\u2019re a heat pump owner in a cold climate, chances are you\u2019ve noticed ice forming on the outside of your heat pump while it\u2019s on. Your first impression may be that something is wrong with the heat pump. After all, how is it supposed to warm your house if it can\u2019t even keep itself from icing over? The truth is that a little ice on your heat pump is nothing to worry about\u2026 until it is. Let\u2019s take a look at what actually causes ice on your heat pump, and whether or not you should worry about it.<\/p>\n
A heat pump has two separate units for distributing heat, an interior unit and an exterior unit. In heating mode, the exterior unit is responsible for siphoning heat from the air and directing inside to be used. It does this by using an evaporator coil to transfer refrigerant from a liquid to a gaseous state. As the refrigerant inside the coils evaporates, it becomes a heat sink for the surrounding air, leeching heat from it. Cold air cannot hold as much water vapor as warm air, so the remaining moisture collects on the coils of the unit. Freezing temperatures being\u2014well\u2014freezing, the moisture soon becomes ice on the pump.<\/p>\n
Yes and no. Yes, if enough ice builds up it can cause issues for the heat pump. Being mostly or completely covered with ice will effectively cut off the exterior part of the heat pump from its supply of thermal energy. This will make it unable to siphon any appreciable amount of heat from the surrounding air. Fortunately, most heat pumps were designed with defrost cycles to melt the ice around the exterior unit. If you see some ice on your heat pump, don\u2019t panic quite yet. Wait and see if it goes away in an hour or two. If the ice level isn\u2019t dropping, or more ice is accumulating on the pump, then it is possible that your heat pump\u2019s defrost cycle is broken.<\/p>\n