What to check on a heat pump, and when

What should you check every month or two?

The air filter is the item that matters most. A clogged filter cuts airflow, raises the electricity used and can freeze the indoor coil in cooling mode. Check it monthly during heavy use and replace or wash it according to the manufacturer's directions. Ductless units usually have a washable mesh filter behind the front panel. Ducted systems share the filter at the furnace or air handler.

Also glance at the thermostat or controller, and note any unusual sounds, smells or error codes. A brief log helps a technician find the pattern later.

What does the outdoor unit need?

• Keep vegetation, leaves and debris at least the manufacturer's stated distance from the coil on all sides.
• Brush loose debris off the fins gently. Never use a pressure washer, which can bend them.
• After snowfall, clear drifts from the sides and top. Do not chip ice from the coil.
• Check that the stand or pad is level and above snow depth.
• Make sure meltwater from the roof does not drip onto the unit or freeze on the path below it.

Normal frost and defrost steam are not faults, as the guide on defrost cycles and noise explains.

What happens during an annual service?

A technician typically inspects the electrical connections, checks refrigerant pressures and temperature differences, cleans the coils, tests the defrost controls and the reversing valve, and checks the condensate drain and the thermostat settings. On ducted systems they may also look at airflow and the duct connections.

Book the visit before the heating season, so any fault is caught before the first cold snap. If you have a gas furnace as backup, the same visit can cover the furnace, which matters for a dual-fuel system. Keep the service records, as warranty terms often require proof of maintenance.

When should you call a professional?

Call if the unit ices up completely, trips breakers, makes grinding or banging noises, short-cycles, or fails to heat when the setpoint is above room temperature. Do not open the refrigerant circuit yourself; refrigerant work needs a licensed technician. A steady drop in comfort or a rise in the electricity bill is also a prompt to check, since the first sign of a faulty heat pump is often a quiet change in use.

What does Drake Landing teach about maintenance?

The Drake Landing system was the opposite of a hands-off appliance. Its collectors, pumps, controls and borehole field all needed attention, and deterioration and maintenance problems from about 2020 are part of why it was wound down. The Energy Centre page describes the equipment involved. A home heat pump is far simpler, but the principle holds: a good design still depends on routine care, as with the ground-source and air-source options alike.

What does neglect cost?

A dirty coil or filter does not usually stop a heat pump at once. It makes the compressor work harder, so the electricity use creeps up, comfort drops and wear builds. Over a few seasons that can shorten the life of the machine and, for a unit under warranty, put coverage at risk if the maker asks for service records.

The costs of routine care are small by comparison. A filter costs little and a yearly visit is a modest bill next to a compressor replacement. When you buy, think about the lifetime view described in the cost guide and plan for upkeep from the start. A reminder in the calendar each autumn and spring is usually enough.

Owners of ground-source systems have a few extra items, such as checking loop pressure and fluid levels, and they should follow the installer's schedule for those. Wherever the heat comes from, a sheet taped inside the utility room listing filter size, service dates and the installer's phone number saves a lot of hunting later.

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