Heated Purge Desiccant Dryers
Ideal for general manufacturing and process industry applications, Van Air HP series externally heated regenerative compressed air dryers provide a low -40°F dew point for superior air line moisture protection, while offering the efficiency of convection-heated desiccant regeneration.
Ideal for general manufacturing and process industry applications, Van Air HP series externally heated regenerative compressed air dryers provide a low -40°F dew point for superior air line moisture protection, while offering the efficiency of convection-heated desiccant regeneration.
All Van Air HP series dryers feature: an isolated external heater for an extra measure of safety; Interlock Logic valve sequencing, for the most reliable tower cycling; and heatless back-up mode, for uninterrupted service while the heater is being serviced.
Principle of operation: Wet compressed air enters the inlet valve and is dried as it flows through a bed of adsorbent desiccant. Dry air exits the outlet valve of the dryer. A small portion (8%) of the outlet air is redirected through the external heater and downward through the off-stream tower to regenerate the desiccant. Wet air is exhausted through the purge valve. The eight-hour NEMA cycle includes four hours of drying, three hours of heating and one hour of cooling per tower.
Features and Benefits
- Standard designs 150 to 5,000 scfm
- On/off switch
- Power on light
- Heater on light
- Activated alumina desiccant
- Desiccant fill/drain ports
- Stainless steel desiccant screens
- Rigid copper pilot air lines
- Control air filter
- Aluminum jacketed heater and tower heated zone insulation
- 460V/3PH/60HZ supply power
- 115V control voltage transformer
- Single external heater
- Emergency heatless back-up mode
- Permanently lubricated inlet transfer valve with a position indicator and depressurization safety
- Purge flow control valve with pressure gauge for flow indication
- Purge exhaust mufflers
- PLC control with manual fast advance & hold switches
- NEMA 1 control enclosure
- Heater power and control power fuses
- Adjustable heater thermostat
- -40°F dew point
- Interlock Logic valve control
- Tower mounted pressure and temperature gauges
- Controlled re-pressurization and depressurization
- ASME coded pressure vessels
- Enamel exterior finish
- Tower lifting lugs
- Fail to switch/pressurize light and common alarm contact
Optional Equipment
- NEMA 4 enclosure
- Color change moisture indicator
- Mounted filters and bypass piping
- Audible alarm
- Full flow safety relief valves
- Digital dew point read out
- Dew point demand switching, recommended to minimize dew point spikes at tower switchover
- Energy saver. A thermostat registers a rise in purge air outlet temperature, which indicates the bed is regenerated, so the heater is turned off.
- High dew point (light and common alarm contact) indicator
- Sequence lights, left right tower regenerating and/or drying
Applications
- Installations where a heated dryer is preferred while minimizing both purge loss and capital investment
- Installations where -40°F pressure dew point is required
