iced over heat pumpUPDATED 1/5/2018 Is Jack Frost nipping at your nose and your heat pump! When the temperature drops during a Maryland winter, we commonly see frost and ice on heat pumps. The heat pump has a defrost cycle to melt the frozen liquid, but sometimes it doesn’t help. If the ice or frost stays on your heat pump for more than a few hours, it’s time to fix the problem.

Frost on heat pump

The outdoor unit of your heat pump may occasionally develop frost when in heating mode. Is this cause for alarm? Well, yes and no. A little frost is okay. A LOT of frost is cause for concern.

The problem is a lot of homeowners never realize their heat pump is iced over because they don’t check it. After all, who wants to go outside in the cold?

Finding the frost is half the battle. Once you find it, there are quick fixes to try.

First of all, when it’s iced over you don’t want your heat pump running. So, turn it off. Otherwise, you’re wasting energy.

Second, check your thermostat settings. When the temperature gets below 30-degrees, use your emergency heat. Otherwise, it’s costing you more money when both run and your heat pump ices over.

How Much Frost is Too Much Frost?

So how does the heat pump ice over? It happens when the outdoor unit of your heat pump is below the dew point of the water vapor in the air. When that outside air comes in contact with the pump surface, the vapor condenses. When the surface is below freezing, the condensed water freezes. That causes frost.

Typically this happens when it’s below 40° F and the relative humidity is about 70% or higher.

Heat pumps have a defrost cycle designed to melt any frost that builds up. However, if you notice frost that doesn’t seem to go away over time, this is cause for concern. Too much frost can prevent air from passing through the fins, greatly diminishing the efficiency of your system.

As a general rule of thumb, if frost stays on the coil for two hours or more, then something is wrong. It’s time to call your Maryland HVAC Repairman to diagnose the problem.

Whole-Home Comfort

As pioneers in Whole-Home Comfort, Minnick’s focuses on how your home performs as a system. Your ductwork, heat pump, and insulation work together to provide comfort and safety. When one is not functioning correctly, all of the others work harder, which leads to more frequent breakdowns and costly repairs. Annual maintenance of your HVAC system ensures your system functions properly.