Ductless Mini-Splits and Their Kin: The Revolution in Variable-Refrigerant-Flow Air Conditioning

New heating and cooling technology arriving from Asian manufacturers is shaking up the world of mechanical systems, offering compelling value and efficiency in a variety of settings. The technology varies in nature and scale, making it applicable to everything from single-family to multi-unit residential buildings and from small to mid-sized commercial buildings. Buildings that require heating and cooling simultaneously in different areas stand to save significant amounts of energy by transferring heat from one area to another.

This technology is fully realized at the commercial level in

variable refrigerant flow (VRF) multi-split systems with up to 20 tons (240,000 Btu/hour or 70 kW) of cooling each; multiple systems can be combined for more cooling. Similar to these are simpler

mini-split systems with two tons (24,000 Btu/hour or 7.0 kW) or less of cooling capacity. Mini-splits don’t have the added efficiency of VRF, but they still represent

an attractive option for smaller spaces in homes or light-commercial buildings.