HI Series Heated Desiccant Dryers 150 through 3000 SCFM
- Rated Flow (SCFM) : 1000
- Avg. Purge Flow scfm m3/hr : 60
- Dimensions (in.) Height x Width x Depth : 114x74x53
- Heater (kW) : 22
- In/Out Conn.(FLG) : 2
- Desic. Weight per Tower (lbs.) : 775
* For total desiccant weight, multiply by two. Desiccant shipped installed on HI-150 through -500. Desiccant shipped separately on larger units. Due to our policy of continuous improvement, dimensions and specifications may change without notice. Request certified drawing for pre-piping. Contact ACS for larger or special models.
RATED FLOWS BASED ON 100 PSIG, 100F INLET AND 100% RH. CONSULT ACS FOR OTHER CONDITIONS.
Main Features
Van Air HI Series internally heated regenerative compressed air dryers supply super dry, -40F/C pressure dew point air for critical requirements for pneumatic instruments, controls and sensitive process air.
All Van Air HI Series dryers feature...
Energy-Saving Flexibility
- Individual heater thermostats and purge flow rates are adjustable for your operating requirements.
Interlock Logic Valve Control
- Patented valve control for the most reliable tower cycling. Each phase of the drying cycle must be completed before the next can begin. Protects against loss of flow or pressure because the offstream tower is always fully repressurized before air flow is redirected to it and a tower can only depressurize after the inlet transfer valve is fully seated.
Desiccant Protection
- Low watt density heaters prevent hot spots which cause desiccant damage and fusing.
Long Valve Life
- Separate valves for hot purge air prevent thermal shock and extend valve life.
Energy-Efficient Regeneration
- Achieved by thorough heat distribution. A multiple-element heater is protected by an isolation tube. Convection heat is produced by the purge air which is pre-heated as it flows down through the isolation tube. As purge air enters the lower part of the desiccant bed, it immediately begins to collect moisture.
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Operation
Wet inlet air flows through the drying tower where moisture is attracted to and adsorbed on the desiccant. A small portion of the dry outlet air (expanded to atmospheric pressure) is diverted to the regenerating tower where it is heated as it flows downward through the heater isolation tube. This air is then directed upward through the bed where it collects
moisture from the desiccant. Wet air is exhausted to atmosphere 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.
Standard Equipment
- 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
- 460V/3PH/60HZ supply power
- 115V control circuit
- Permanently lubricated inlet transfer valve w/position indicator and depressurization safety
- Purge flow control valve w/pressure gauge for flow indication
- Purge exhaust mufflers
- Mechanical timer
- NEMA 1 control enclosure
- Main power and control power fuses
- Heater contactors
- Heater safety guards
- Adjustable heater thermostats
- -40F/C pressure dew point
- Interlock Logic valve control
- Tower mounted tower pressure and temperature gauges
- Controlled repressurization
- ASME code pressure vessels
- Enamel exterior finish
- Tower lifting lugs
Optional Equipment
- NEMA 4 control enclosure
- Color change moisture indicator
- Mounted filters and bypass piping
- Audible alarm
- Full flow safety relief valves
- Digital dew point readout
- Dew point demand switching*
- Energy saver*
- Failure to switch/purge/pressurize
- High dew point indicator
- * Energy saver or dew point demand switching is recommended to minimize temperature spikes at tower switchover.
Dew Point Demand Switching
Holds the drying tower on stream until the desiccant bed is fully saturated. At this point, the moisture sensor signals the dryer controls to switch the process flow to the dry tower and regenerate the wet tower. Includes indicator light for in-tower high dew point with dry contacts for remote indication.
Energy Saver
Reduces the heating cycle to match actual moisture loading conditions for operation under low flow or low inlet moisture loading conditions, thus lowering operating costs. A rise in purge air outlet temperature indicates the bed is regenerated, so the heater is turned off.
Failure to Switch/Purge/Pressurize
Pressure switches sense offstream tower pressure. Failure to switch is indicated when the inlet valve does not shift, or when the tower does not repressurize.
High Dew Point Indicator
Light is activated when the outlet dew point is higher than the set point. Includes contacts for alarm or remote indicator.
Filtration Recommendations
Regenerative dryers must have clean, oil-free inlet air!
Lubricated compressors
Dryer must be equipped with coalescing prefilters as shown in our filter brochure. Failure to do so may result in hazardous operating conditions and voids warranty. A high-temperature afterfilter is recommended to remove desiccant particles.
Non-lubricated compressors
A coalescing or particulate prefilter is recommended to keep pipe scale and dust from entering the dryer. A high temperature afterfilter is recommended to remove desiccant particles.