How does a ductless heat pump work?

Ductless heat pumps are reversible, 2-way heat pumps that use electricity to transfer heat between outdoor and indoor air by compressing and expanding a refrigerant. Using a refrigerant vapor compression cycle, like a common household refrigerator, ductless heat pumps collect heat from outside the house and deliver it inside on the heating cycle, and vise versa on the cooling cycle.

Ductless heat pumps use variable speed compressors with “inverter technology” (AC to DC) to continuously match the heating/cooling load, avoiding the on/off cycling of conventional electric resistance and central heating systems that is associated with uncomfortable temperature variations and high energy consumption