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  • 50 SCFM capacity
  • 150 PSI max inlet pressure
  • 120°F max inlet temperature
  • Spring loaded desiccant beds
  • Compact design with versatile mounting and installation options
  • Fully re-pressurizing design
  • Standard NEMA 4X electrical rating
  • -40° F/C pressure dew point
  • 240/1/60 voltage
  • ISO 8573.1 Class 2


The Altec AIR HR7-21, 50 SCFM, 240 VAC heatless regenerative desiccant dryer utilizes pressure swing adsorption (PSA) technology to remove water vapor from compressed air. The inlet shuttle valve moves the air into the online desiccant tower where a majority of the water vapor is removed. The dry air then passes through the outlet shuttle valve and on to the application. A purge orifice in the outlet shuttle disk allows some of the dry air to be redirected back through the offline tower where the moisture can be purged. The solid-state timer controls the process by opening and closing the solenoid valves.

The HR Series features spring loaded desiccant beds that help to extend the life of the desiccant that is in each tower. The compact design combined with the simple and versatile mounting allows for a wide variety of installation options. The fully re-pressurizing design creates steady outlet pressure and flow.