Quincy QGS 10 Instruction Book page 76

Testing
The valve can be tested on a separate compressed air line.
Before removing the safety valve, stop the compressor (see section Stopping), close the air outlet
valve, switch off the voltage, open drain valves (4) (tank-mounted units) and the manual drain
valve (5) (if fitted - on floor-mounted units) and unscrew filler plug (3) one turn to permit any
pressure in the system to escape.
74
Oil filler plug
If the valve does not open at the set pressure stamped on the valve, replace the valve.
No adjustments are allowed. Never run the compressor without a safety valve.
Instruction book
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