The CPX Refrigerated Air Dryers For All Applications Sized to handle 12 to 2966 cfm, the CPX dryers fit any application. Extremely quiet and reliable, CPX dryers deliver dry air with minimal pressure drop. These dryers are machines designed for treating compressed air. By using the refrigerant characteristics of certain fluid, these dryers lower the temperature of the compressed air, causing water vapor to condense and discharge prior to it entering any distribution system.