Ductless, mini-split-system heat pumps are advantageous for retrofit add-ons to houses with non-ducted heating systems, room additions where extending or installing distribution ductwork is not feasible, and very efficient new homes that require only a small space conditioning system. They are also flexible for zoning or heating and cooling individual rooms, and many models can have multiple indoor air-handling units connected to one outdoor unit.

Mini splits have two main components — an outdoor compressor/condenser and an indoor air-handling unit. A conduit links the outdoor and indoor units, housing the power cable, refrigerant tubing, suction tubing, and a condensate drain.

Many models can have as many as four indoor air-handling units connected to one outdoor unit, depending on how much heating or cooling is required for the building or each zone. Each zone has its own thermostat, allowing for energy and cost savings by only conditioning occupied spaces.

Mini splits are a good choice for houses with non-ducted heating systems, room additions where extending or installing distribution ductwork is not feasible, and very efficient new homes that require only a small space conditioning system. They are also suitable for zoning or heating and cooling individual rooms.

Mini splits make good retrofit add-ons to houses with non-ducted heating systems, such as hydronic (hot water heat), radiant panels, and space heaters (wood, kerosene, propane).