4 – 11
VSG/VSSG • Installation, Operation and Maintenance Manual •Vilter/Emerson • 35391STG
NOTICE
To purge the compressor unit using a dry gas (i.e.
methane), a purge line must be installed. If there is
not enough purge pressure, connect purge line to a
lower pressure line or to atmosphere.
The purge line,
associated valves and gauges are not provided from the
factory and must be installed by the customer.
1. Refer to Figure 4-10 for recommended purge line
design.
2. Press “Stop” button to stop compressor unit, see
Figure 4-11.
3. Allow pressure in compressor unit to equalize to
suction pressure, see Figure 4-12.
4. Close suction and discharge shut-off valves to
isolate the compressor unit from house system.
Lockout/tagout valves.
5. Close any other valves that may feed gas or oil to
the compressor and oil separator.
Section 4 • Operation
Purging with Dry Gas
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.
Figure 4-10. Customer Purge Line
PI
002
Shut-off Valve
Check Valve
Shut-off Valve
Pressure Indicator
Drain Valve
FG
001
TE
001
PT
001
BLEED
DRAIN
PT
002
BLEED
TE
004
QE
101
QE
102
QE
103
TE
005
1000W
1000W
1000W
LG
001
LG
002
OIL CHARGE
TE
002
PI
002
DRAIN
DRAIN
VENT
TE
003
QE
007
TE
007
OIL SEPARATOR
COMPRESSOR
MOTOR
REMOTE
OIL COOLER
COALESCING OIL
RETURN LINE
PURGE LINE
PRESSURE
EQUALIZING LINE
SUCTION INLET
DISCHARGE OUTLET
To Lower Pressure Line or
Atmosphere. See NOTICE.