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  • 12 SCFM
  • 120°F max inlet temperature
  • 150 PSI max pressure
  • Solid-state timer with built-in memory
  • Fixed orifice purge control
  • Dual inlet and outlet port configurations
  • -40°F standard outlet dew point
  • 240/1/60 voltage
  • Moisture indicator included


The Altec AIR VSA4-21M, 12.0 SCFM Heatless Regenerative Desiccant Air Dryer utilizes Pressure Swing Adsorption (PSA) technology. Compressed air is passed through the inlet to one desiccant tower where water vapor is removed. The dry air then continues to the outlet side of the manifold and out to the application. A portion of the dried air is expanded through an orifice and directed back through the offline desiccant tower where the accumulated moisture is purged. The solid-state timer and two solenoid valves reverse the process.