Hot, compressed air enters the air dryer through the inlet port. As the hot air enters the dryer, the air expands, oil and water vapor condense, and accumulate in the sump. The air passes through 3 filters and a cloth bag that removes carbon and other contaminates. Air vapor continues to condense as air travels to the desiccant bed housed in the cartridge. The clean dry air is then directed to the vehicle air system through the outlet port and simultaneously to the purge tank through the purge port.

When the air system reaches the governor regulated cut-out pressure (typically 120 psi), the air dryer unloader valve opens via an air signal received from the air system governor. The governor will also simultaneously signal the compressor to stop compressing air. The air dryer check valve is closed via back pressure from the wet tank. This rapid action causes a sudden discharge of air through the exhaust port of the dryer. The filtered, dried purge air, which has accumulated in the isolated purge tank, slowly bleeds back through the air dryer. This action regenerates desiccant, cleans filters and expels the contaminants out the exhaust port. This completes the regeneration cycle.

Additionally, the TURBO-2000 air dryer incorporates a TURBO valve and a pressure differential check valve. The TURBO valve ensures engine boost pressure cannot escape out the air dryer's exhaust port during the stand-by mode of the compressor. The differential check valve maintains system air pressure within the air compressor discharge line. These 2 valves ensure full turbo boost pressure is checked and available at all times during the operation of the vehicle.

When the air system drops to the governor regulated cut-in pressure (typically 95 psi), the air dryer unloader valve closes as the unloader line pressure evacuates through the exhaust (EXH) port of the governor. The compressor is signalled to proceed pumping.