VRV and VRF are interchangeable terms. These units usually have several (or many) indoor units powered by a single outdoor compressor. These systems are similar to a multi-split systems and can have the same internal components as a multi-split. The difference with these units is the outdoor units can run at varying speeds depending on requirements, whereas most air conditioning compressors either run at a single speed or are turned off.

VRF units include an inverter and DC motors which facilitate running at different speeds. Variable compressor motor speed and means variable refrigerant flow. By operating at varying speeds, VRF units work only at the required rate to maintain the environment, allowing for substantial energy saving.