Scroll compressors, also known as spiral compressors, belong to the rotary-type displacement compressors. These consist of a spiral that is attached to the casing and an eccentrically moving spiral, which is driven by an electronic motor. The spirals rotate in opposite directions, resulting in the air being sucked into an opening in the casing, where it is subsequently compressed. The compression procedure is oil-free.

Once the movable spiral begins rotating, air is aspirated. The aspirated air is channeled to the center by the rotating spiral, where a non-return valve and an outlet opening are situated. Within 2,5 rotations, the compression process is concluded, and a continuous, pulsation-free volume flow is achieved.

Suppliers generally enumerate three advantages of scroll compressors, namely that the small amount of moving parts renders them practically maintenance-free, the compression is relatively vibration- and noiseless, and, above all, no oil is required for this type of compression.