Product Manual

Table Of Contents
Reference Designation Reference Designation
1 Compressed air inlet 7 Electrical control line
2 Dryer controller 8 Flow restriction
3 Left desiccant tower 9 Check valve
4 Right desiccant tower 10 Selector valve
5 Compressed air outlet 11 Pneumatic silencer
6 Flow line 12 Solenoid valve
The operation cycle of the dryer is repetitive and is controlled by a factory set timer. While the desiccant in
one tower dries the compressed air, the desiccant in the second tower is being regenerated. Regeneration of
the desiccant is achieved by means of purge air from the drying tower.
The compressed air entering the dryer is led to one of the towers by means of the bottom selector valve.
The position of the selector valve depends on the position (activated or not) of the solenoid valves. As the
air flows upwards through the tower, the desiccant adsorbs the water vapor and the compressed air is dried.
When it reaches the top of the tower, the dried air leaves the dryer via the check valve.
A small portion of the dried air passes a nozzle, expands to atmospheric pressure and flows downwards
through the other tower, regenerating (drying) the desiccant. The size of the nozzle depends on the
operating pressure. Alternative nozzles for use at other operating pressures are available. Please consult the
spare parts list for ordering information. The regeneration air is released via the corresponding solenoid
valve and a silencer. The solenoid valves are controlled by the timer.
After a preset time interval, the function of the towers is reversed. The fully regenerated tower will now dry
the air, while the desiccant in the other tower will be regenerated.
When the compressor stops, the drying cycle stops as well: purge air flow stops, both solenoid valves are
closed. When the compressor restarts, the drying cycle will resume where it was stopped.
Control panel
Reference Designation Reference Designation
1 LED <Power On> 7 Air outlet
2 LED <Right tower drying> 8 Inlet selector valve
Instruction book
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