Keeping Your Heat Pump Clear of Snow and Ice

4 min read · Thames Valley Snow, London, Ontario

Why snow matters for a heat pump

An air-source heat pump moves heat from the outdoor air into your home. To do that, the outdoor unit has to pull a large amount of air across its coil. If snow drifts against the sides, piles up underneath, or a block of ice forms on top, airflow drops and the system works harder for less heat. Many systems then lean more on backup electric or gas heat, which costs more to run.

What is normal: the defrost cycle

In cold, damp weather a light layer of frost forms on the outdoor coil. Heat pumps handle this on their own with a defrost cycle: the unit pauses heating for a short time, the fan may stop, and you may see steam rising from it. That is normal. Water from the defrost drips down and needs somewhere to drain, which is one reason the unit should sit up off the ground.

What is not normal is a unit that stays coated in thick ice for hours, or ice that keeps building on top. That can point to a drainage problem, water dripping from the roof onto the unit, or a fault. Call your heating contractor rather than trying to fix it yourself.

Safe ways to keep it clear

• After a snowfall, brush loose snow off the top and away from the sides with a soft broom.
• Clear the ground around the unit so air can flow in and meltwater can drain away. Many installers recommend at least about 30 cm of open space around it; check your manual.
• Never chip or hammer ice off the coil or fins. They bend and puncture easily. Let the defrost cycle do its job, or call a technician.
• Do not pour hot water on the unit. It can refreeze into thicker ice around the base.
• If roof runoff drips onto the unit, ask about a small cover or a gutter fix. Covers should be designed for heat pumps, because wrapping or tarping the unit blocks airflow.

Raise it and mark it

Most outdoor units sit on a pad or wall bracket to keep them above typical snow and let water drain. If yours sits low, talk to your installer about raising it before winter. Then put a tall stake or reflective marker beside it. Under fresh snow the unit can look like just another drift, and a marker shows anyone clearing the property exactly where it is.

Where snow should not go

The biggest risk to a heat pump in winter is often snow piled on purpose. A shovelled walkway that runs past the unit, a snowblower chute pointed the wrong way, or a roof dump can bury it in minutes. Pick spots for your own snow piles that are well away from the unit, from dryer and furnace vents, and from window wells.

When you book a snow service, mention the heat pump, its location, and anything else near it such as a gas meter or vent pipes. Showing where it is lets the crew pile snow well away from it. Crews do not clear, cover or service the heat pump itself; that stays with you and your heating contractor.

Freezing rain and refreeze

Freezing rain can coat the unit in a shell of ice and make the path to it slick. After an ice event, check the unit from a safe footing and call a technician if it stays iced over. Seasonal salting ($175, including freezing rain and refreeze visits) keeps the driveway and walks safer, so checking the side of the house is less of a risk.

A simple winter routine

• Before winter: clear leaves from the base, check the drain path, place a marker.
• After each snowfall: brush the top and sides, clear a gap around the base.
• After freezing rain: look for heavy ice and call for service if it does not clear.
• All winter: keep snow piles, roof dumps and shovelled snow away from the unit.

Let us handle the driveway

A seasonal plan clears your driveway automatically from December 1 to March 31 whenever 5 cm or more falls, clears the City windrow, and sends a timestamped photo after every visit. Walkway and steps clearing from $150 gives you a safe route to the side of the house. See residential snow removal and keeping furnace vents and gas meters clear.

Every Thames Valley Snow quote is measured from City of London maps and aerial imagery, and you get a fixed price within 1 business day. Ask for a free quote, or call or text (548) 888-8702.