Inverter compressors allow air conditioners to control the speed of the motor, which in turn enables them to deliver variable capacity. This means the unit can operate in a way that better suits the conditions they are working in – for example, if the unit is treating a space that has conditions suited to a smaller unit than the one installed, the air conditioner can ramp its capacity down to better match the space.

This is in contrast to traditional fixed speed compressors, which can only operate by turning on at maximum capacity, or off entirely. Typically, inverter compressors allow air conditioners to deliver increased energy efficiency.