A common misconception in the field is that DCI’s compressor is not purging correctly because it does not purge once the motors turn off. The DCI compressor’s drying system is designed to purge based on a time operated purge solenoid. It is preset at the factory to purge every 7 minutes for 10 seconds. This is the optimal time to have your compressor purge to ensure dry air. The purge valve is located below the coalescing filter assembly. To confirm your purge valve is set to purge every 7 minutes for 10 seconds, locate the purge valve. The left knob should be set at 10 (turned to the far right) and the right knob should be set at 7 (set the arrow on the knob in-between 5 and 10).
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Response: I have a doctor with this on a non DCI compressor. Has a 3 stage filter with desiccant on the output. Is the purge for tank water ? Haven’t traced the wire is it normally on? Where is the tech sheet located?  Bob

Hi Robert,
On our compressor the timed purge is used to purge air through the dessicant periodically to keep the dessicant beads dry.  However I have talked to more than a few people that have used this solenoid to purge water from tanks on units that built up lots of water in the tanks.  If used for an application like that it would be good to also put a filter in front of the purge solenoid to prevent any debris from in the tank getting into the solenoid.  Something like our #2009.
  The solenoid is a normally closed solenoid, it is wired to power source that is on when the compressor is on.  The timer an the unit then activates based on the timing selected and sends power to the solenoid coil, thus opening the valve.
I will see what we have in the way of a tech sheet and post it on here.  In what way is the solenoid installed on the compresor you are working on?