Quincy QGS 10 Rotary screw would not cut in, now it won't turn on.
(Perkins, MI USA)
We have a 3 phase Quincy QGS 10 Rotary screw compressor. Compressor is just over a year old. We had a problem with it not cutting in, so we shut it down to inspect the pressure switch, connections, etc.
Now it will not turn on. The pressure switch (condor mdr1) only has two wires going to it from the main control box.
I can manually depress the main motor contactor and it seems as though it is stuck in an unloaded state (motor/screw turning but not compressing air). The on switch will not activate the contactor to start the motor.
Any ideas to point us in the right direction would be helpful.