Heat Pump Types and System Designs

A heat-pump label describes only part of a home-heating system. Start by separating the heat source, the way heat reaches rooms, the services the system provides, and the parts of the home it is designed to cover. Those choices affect site work, comfort, controls, and what remains of your current heating system.

Choose the comparison that fits your decision

• Air-source vs. ground-source heat pumps for a retrofit home compares outdoor-air equipment with systems that use a ground loop or water source.
• Ducted vs. ductless heat pumps for an existing home looks at existing ducts, room layout, indoor-unit placement, and mixed arrangements.
• Air-to-air vs. air-to-water heat pumps explains how heat is delivered and how that affects radiators, cooling, and domestic hot water.
• Whole-home vs. partial-load heat pumps helps define whether a heat pump is intended to serve the whole home or work alongside an existing system.
• Gas-fired absorption heat pumps explains how a gas-driven absorption cycle differs from an electric heat pump paired with a boiler.

Keep the system questions separate

“Air-source” and “ground-source” describe where a heat pump exchanges heat. “Air-to-air” and “air-to-water” describe what it heats inside the home. “Ducted,” “ductless,” and “hydronic” describe ways that heat is distributed. A proposal may combine choices from several of these groups.

A label does not establish that the system will heat every room, serve household hot water, meet the home’s heat loss on a cold day, or cost less to operate. Ask for the design assumptions and the equipment data behind those conclusions. Local climate, building layout, energy prices, product combinations, and requirements also matter.

Start with the rooms and services you want to cover, then compare system designs that can serve them. Have a qualified local professional assess loads, distribution, equipment matching, controls, and any site work before making a final selection.