4 – 10
VSG/VSSG • Installation, Operation and Maintenance Manual •Vilter/Emerson • 35391STG
Section 4 • Operation
NOTE
Purging is performed through the suction oil charging
valve so that trapped gas can be pushed out of the
compressor. This will help minimize metal surface
oxidation of the compressor (due to the gas) while not
in service.
9. Purge compressor unit for 10 minutes. Check dis-
charge pressure on PLC main screen to make sure
pressure is increasing.
10. Close discharge bleed valve while still purging.
11. Observe discharge pressure through the PLC main
screen. Allow pressure to build to approximately 10
psig.
Equalizing Solenoid
for Suction Bypass
Figure 4-8. Equalizing Solenoid
Figure 4-9. Suction Oil Charging Valve and Discharge Bleed Valve
12. Once pressure is reached, stop purging and close
suction oil charging valve. If pressure is greater
than 10 psig, crack open discharge bleed valve,
as needed, to slowly bleed the system to approxi-
mately 10 psig.
13. Wait 10 minutes to make sure there are no leaks
and that the pressure is holding. If the unit does not
hold pressure, check all isolation valves for correct
operation; discharge, suction and oil return valves.
14. Remove purging hose from suction oil charging
valve.
CAUTION
With a purged system, when getting the compressor
unit ready for start-up, it is important to slowly open
the suction valve to prevent a sudden rush of gas
and oil. Failure to comply may result in damage to
equipment.
View Rotate 90°
View Rotate 90°
Suction Oil
Charging Valve
Discharge
Bleed Valves
