Heat pump basics for homeowners

How a heat pump works

Instead of burning fuel to make heat, a heat pump moves heat. In winter it pulls heat from the outdoor air and brings it inside; in summer it runs in reverse to cool the house. Because it's moving heat rather than creating it, it can deliver more heat energy than the electricity it uses.

Do they work in cold weather?

Modern cold-climate heat pumps are designed to keep heating well below freezing. Their efficiency drops as it gets colder, so in very cold regions some homes pair a heat pump with a backup, such as electric resistance heat or a gas furnace. A good contractor will size the system for your area's typical winter lows.

Ducted or ductless?

Ducted heat pumps

These connect to your existing ductwork, much like a central air system, and are a common replacement for a furnace and air conditioner.

Ductless mini-splits

These use small indoor units mounted on walls or ceilings, connected to an outdoor unit. They're a good fit for homes without ducts, additions, garages, or rooms that are always too hot or too cold.

Things to consider

• Your current fuel and rates: the savings depend on what you pay for electricity compared with gas, propane, or oil.
• Electrical capacity: some homes need an electrical panel upgrade.
• Rebates: many utilities and states offer incentives for efficient heat pumps.
• Installer experience: proper sizing and installation matter as much as the equipment brand.

Questions to ask before you buy

• Is this model rated for cold climates, and how will it perform on our coldest days?
• Will you do a room-by-room load calculation?
• Do I need a backup heat source?
• Which rebates apply, and will you help with the paperwork?