Best thermostat settings for a heat pump in winter

Why does a heat pump need different thermostat habits?

A furnace delivers a lot of heat quickly, so turning the thermostat down at night and up in the morning works well. A heat pump delivers moderate heat steadily and is most efficient when it runs at a low, even speed. Asking it to raise the house several degrees in a short time pushes it to its limit, and on a cold morning the thermostat may call for backup heat to catch up.

Backup heat is the costly part. The guide to heat pump backup heat explains why resistance elements use far more electricity per unit of heat than the heat pump does. Keeping the system out of that mode is the main goal of good settings.

What temperature should you set?

Pick a comfortable temperature for the hours you are home and hold it. Many energy-efficiency guides suggest an occupied setting of around 20 to 21 degrees Celsius, and each degree you lower it saves some energy, so the right figure is the lowest one you find comfortable. If you want a daytime or overnight setback, keep it small, one or two degrees, and ease back up gradually.

Some modern thermostats and variable-speed heat pumps handle gradual recovery by design. Check whether yours has a mode that raises the temperature in steps or learns how long recovery takes. The savings of a smart model are covered in smart thermostat savings in Canada.

What do auxiliary and emergency heat settings mean?

Many thermostats have a few modes. In normal heating the heat pump runs, and the backup element or furnace joins in automatically when the pump falls behind. In emergency heat mode, the heat pump is locked out and only the backup runs. It is meant for a failed outdoor unit, not for everyday use, because it costs much more to operate.

If the thermostat shows an auxiliary heat light often in mild weather, something is off. The setpoint may be jumping, the lockout temperature may be too high, or the heat pump may be undersized or faulty. Ask your installer to review the settings, and see heat pump balance point for the temperature below which backup is expected.

Which thermostat features are worth having?

• Compatibility. Choose a model made for heat pumps, with the right wiring and the ability to control backup heat separately.
• Staged or gradual recovery. This limits the use of backup during setbacks.
• Outdoor lockout for backup. The control stops the elements from running above a set outdoor temperature.
• Remote access. Useful for a second home or a cottage, where you can keep the house at a safe minimum temperature.

Cooling in summer follows the same rule: steady settings and modest changes. Ductless systems use their own remote controls, and the same principles apply there.

How do settings fit into a wider plan to cut heating costs?

Thermostat habits are one lever among several. Air sealing, insulation, and clearing snow from the outdoor unit make the biggest difference to how often the system works hard, and the guide on how to lower your heating bill in winter lists the main steps. A seasonal routine of filter changes and visual checks is in the winter home energy checklist. If the system seems loud or ices up on a cold morning, check the defrost and noise guide before changing any settings.

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