Copeland Scroll® compressors utilize two concentric scrolls, identical in size, one inside the other. One scroll remains stationary as the other orbits around it. This movement draws gas into the compression chamber and moves it through successively smaller “pockets” formed by the scroll’s rotation, until it reaches maximum pressure at the center of the chamber. There, it’s released through a discharge port in the fixed scroll. During each orbit, several pockets are compressed simultaneously, so operation is virtually continuous.