The Parker PRD Series Refrigeration Air Dryer is designed to improve compressed air system efficiency and productivity by reliably removing moisture from compressed air streams. These dryers are particularly suited for general industrial and factory automation applications, providing dependable air treatment for oil-free pneumatic systems.
Refrigeration air dryers operate by cooling compressed air to condense and remove water vapour. The Parker PRD Series typically delivers pressure dew points between 35°F (1.7°C) and 50°F (10°C), ensuring moisture is effectively removed while preventing freezing within the system. This dew point range is ideal for general-purpose compressed air systems where protection from condensation, corrosion and moisture damage is required.
The drying process is achieved through a sequence of heat exchange stages. First, incoming compressed air is pre-cooled in a heat exchanger, reducing the temperature before entering the refrigeration stage. The air is then further cooled by the refrigeration circuit, allowing moisture vapour to condense and separate from the compressed air stream. Finally, the air is reheated before exiting the dryer, preventing pipe sweating and condensation within downstream distribution piping, particularly in humid environments.
The PRD Series uses a non-cycling direct expansion refrigeration system, where the compressed air and refrigerant interact through a heat exchanger to achieve cooling and moisture removal. While non-cycling dryers run continuously for consistent performance, they provide simple, reliable operation with minimal system complexity.
A patented PlusPak 3-in-1 aluminium heat exchanger design integrates multiple heat exchange processes within a compact unit. This design improves heat transfer efficiency while reducing pressure losses across the dryer. Additionally, the system includes a zero air loss condensate drain, which removes collected moisture without wasting compressed air, improving overall system efficiency.
PRD Series dryers are available with multiple connection sizes and electrical configurations, supporting compressed air flows from 10 to 250 SCFM (17 to 425 m³/h). Their robust construction, efficient moisture removal and low pressure drop make them a practical solution for maintaining reliable compressed air quality in a wide range of industrial environments.