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COMPRESSOR CAPACITY CONTROL - TURN VALVE UNITS ONLY
The capacity of the compressor is controlled by the action of the turn valve and the compressor inlet
valve.
The turn valve controls compressor delivery to match demands of 40% to 100% of the compressor’s
maximum capacity. The inlet valve throttles to control compressor delivery to match demands of 0% to
40% of the compressors maximum capacity.
Example with normal setting of 100 PSIG:
Compressor Delivery
Capacity
Inlet Valve
Turn Valve
Discharge Manifold
Pressure
Full Open Closed
100
70% Open 50%
Open
100
40% Open Full
Open
100
30% Closing
Full
Open
103
20% Closing
Full
Open
103
0% Closed
Full
Open
103