The function of a compressor is to remove the vapor produced by the evaporator and to deliver it at a required higher pressure. The compressor can be compared to a heart pumping the blood (the refrigerant) inside the body (the compression cycle). In the basic compression cycle, the compressor is positioned between the evaporator and the condenser. Compressors can be installed in either single or multistage configuration, and can be connected to each other in series or in parallel.
This chapter discusses the most common working principles of different compressors, and presents the intimate relationship between the compressor and the evaporator.