Minisplit

A minisplit, short for mini-split air conditioning, is a ductless heating and cooling system that uses an outdoor condenser or compressor connected by refrigerant lines to one or more indoor air-handling units. Because it does not require ductwork, it is commonly used for retrofits, additions, or rooms without existing ducts.

The system typically comprises an outdoor unit housing the compressor and condenser, and one or more indoor units such as wall-mounted, ceiling cassette, floor-mounted, or concealed ducted units. Each indoor unit is controlled individually, often via remote or smart thermostat, allowing zone-specific temperature control. The indoor and outdoor sections are linked by insulated copper refrigerant lines and a condensate drain.

Two main configurations exist: single-zone systems with one indoor unit, and multi-zone systems with multiple indoor units connected to a single outdoor unit. Multi-zone models can maintain different temperatures in different rooms.

Advantages include high energy efficiency, the ability to zone spaces, absence of ductwork (reducing energy losses), compact outdoor footprint, and quiet operation. They are relatively easy to install in spaces where ductwork would be impractical and are suitable for retrofits, new builds, or expansions.

Limitations: higher upfront cost per BTU, reliance on outdoor unit for all zones, may be less effective in very cold climates unless paired with cold-climate technology, refrigerant handling considerations, and ongoing maintenance of indoor units and condensate drainage.

Installation should be performed by a licensed HVAC professional to ensure correct refrigerant charge, electrical connections, and system commissioning.