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VSG/VSSG • Installation, Operation and Maintenance Manual •Vilter/Emerson • 35391STG
Purging with Dry Nitrogen
Purging is recommended if the compressor will be
inactive for 12 hours or more. For additional long
term storage information, refer to Long Term Storage
Recommendations in Section 3.
PREPARATION
WARNING
When working with LFG, NG or other dangerous
or
fl
ammable gases, ensure there are adequate
ventilation and vapor detectors. Refer to national
fi
re
and building codes. Failure to comply may result in
serious injury or death.
WARNING
When working with pressurized system, always wear
safety glasses and/or face shield. Failure to comply
may result in serious injury.
1. Press “Stop” button to stop compressor unit, see
Figure 4-7.
2. Allow pressure in compressor unit to equalize to
suction pressure, see Figure 4-8.
3. Close suction and discharge shut-off valves to
isolate the compressor unit from house system.
Lockout/tagout valves.
4. Close any other valves that may feed gas or oil to
Figure 4-7. PLC Main Screen
Stop
Button
Discharge
Status
the compressor and oil separator.
5. Slowly open suction oil charging valve to depres-
surize compressor unit to atmosphere, see Figure
4-9. Keep valve in open position.
NOTE
Plugs are installed on bleed valves. Remove and install
plugs prior to and after bleeding. Ensure to keep valves
closed when removing and installing plugs.
6. Open discharge bleed valve to allow nitrogen to
purge through compressor unit, see Figure 4-8.
7. Refer to PLC main screen for discharge pressure
when purging.
PURGE
CAUTION
Do not purge compressor unit with oxygen. Failure to
comply may result in damage to equipment.
CAUTION
Do not allow compressor to spin while purging.
Regulate purging pressure as needed. Failure to
comply may result in damage to equipment.
8. Connect purging hose from nitrogen cylinder to
suction oil charging valve.
Section 4 • Operation