Heat pumps in London, Ontario

What a heat pump actually does here

A heat pump is an air conditioner that can run backwards. In summer it takes heat out of the house, in winter it takes heat out of the outdoor air and brings it in. That sounds like a trick in February, and it is the part people struggle with, so here is the honest version for this climate.

London gets down into the minus twenties on roughly four nights a year, usually in January or February. The rest of the heating season sits well above that. A modern cold climate heat pump handles the great majority of those hours perfectly well, and the gas furnace only has to carry the handful of genuinely cold nights. That pairing is called a hybrid or dual fuel system, and for a house that already has gas it is usually the sensible answer rather than ripping the furnace out.

Where a heat pump makes real sense

• Your air conditioner is due anyway. This is the big one. If you are replacing the outdoor unit regardless, the extra cost of making it a heat pump instead of a plain AC is much smaller than the headline figures suggest.
• You are on propane or oil. Common enough just outside the city. Propane in rural Ontario runs consistently dearer than natural gas, and that is exactly the situation where a heat pump changes the monthly number rather than just the marketing.
• There is no ductwork. A ductless heat pump gives you heating and cooling in the rooms you use without tearing the house apart.

Where I will tell you not to bother

If you have a fairly new high efficiency gas furnace, a working air conditioner, and cheap natural gas, a heat pump is not going to pay you back any time soon. I would rather say that on the phone than sell you one and have you work it out later.

Sizing, and why it matters more here than anywhere

An oversized heat pump is worse than an oversized furnace. It short cycles, it never settles into the efficient part of its range, and it is noisier. I would rather spend twenty minutes working out what your house actually needs than sell you the biggest one on the list.