
Like a refrigerator or air conditioner, heat pumps use refrigerant, a compressor, and various valves to move heat from one area to another. Mini-split heat pumps (MSHPs), or ductless heat pumps, move heat into a home or business during the heating season and provide cooling or dehumidification in the summer. These heat pump appliances costs less to operate than burning oil or propane and provide cooling for less than conventional air conditioners. Insource Renewables is a Fujitsu Elite Dealer for heat pump systems across Maine.


Single-zone heat pump units have one outdoor unit and one indoor unit. These ductless heat pump systems are the most efficient units for heating your home or business and often provide the best return on investment. The indoor unit uses a fan and a heat exchanger – much like the radiator in your car – to distribute heat or to provide cooling in the area served by the unit. These heat pump units are rated to outdoor temperatures of -5F and will work to -15F. Since it is more difficult to extract heat from the outdoor air as it gets colder, the output of these units decreases as it gets colder outside. As a result, auxiliary heat – such as a furnace, boiler, or electric heat – is often necessary to maintain comfort as the outdoor temperatures drop.

Indoor mini split heat pump units come in a variety of models. The most popular model is a wall-mounted unit that is installed near the ceiling. There are also floor mounted units that may be used when there is limited space and the unit needs to be below a window or for aesthetics. Other heat pump units include cassettes that can be installed in a drop ceiling and models that utilize ductwork for distribution.

Multi-zone ductless heat pump systems have one outdoor unit and multiple indoor units. While these systems are less efficient than single-zone units, they provide the benefit of heating and cooling various rooms in the house without requiring multiple outdoor units. Like single-zone units, the performance of these units decreases as the outdoor temperatures falls.
Multi-zone mini-split heat pumps may make sense if a home is heavily partitioned or if multiple air conditioners can be replaced by the heat pump.

We are committed to providing long-term solutions to our clients’ energy needs. The expected lifespan of mini-split heat pump systems is 12-15 years, and we do everything within our control to minimize long-term heat pump service costs.
That said, all mechanical equipment will ultimately need repair. A circuit board may fail or the compressor may need to be replaced. The manufacturer provides a warranty on parts, and we offer a 3-year labor warranty. We service the equipment we install and service MSHPs that have been installed by others.