Which type of compressor uses a rotating action to compress refrigerant?

• A. Rotary compressor
• B. Reciprocating compressor
• C. Centrifugal compressor
• D. Screw compressor

Answer: (A)

Compression in this type is achieved by a rotating set of internal elements that form sealed pockets and shrink them as they turn, pushing refrigerant from the intake toward the discharge in a smooth, continuous flow. That rotating action to compress the refrigerant is the defining feature of a rotary compressor.

Reciprocating compressors rely on a piston moving back and forth in a cylinder to perform suction and compression in cycles, which is a linear, not continuous, motion. Centrifugal compressors increase pressure primarily through high-speed spinning and diffusion, using kinetic energy rather than rotating pockets that directly compress in a sealed chamber. Screw compressors also rotate, using intermeshing rotors to trap and move refrigerant, but the hallmark emphasized here is the direct rotating action that produces compression in sealed pockets, which aligns with the rotary design.