Cycling Refrigerated Air Dryers generally utilize some sort of thermal mass that the dryer cools to a certain temperature then the refrigeration compressor shuts off. Air passes through this chilled thermal mass cooling the air and allowing for water to condense out of the air stream. Once the thermal mass temperature rises, the refrigeration compressor comes back on and chills the thermal mass again. By not having the refrigeration compressor constantly running, energy is saved reducing your energy costs. Cycling Air Dryers should be used with Variable Speed Rotary Screw Air Compressors or Fixed Speed Air Compressors that do no see a constant demand.