GMV5 DC INVERTER VRF UNITS SERVICE MANUAL
201
6) After a required amount of lubricant is added, close the oil checking valve to ensure tightness.
Note: Lubricant is of great importance to the normal running of compressors. You should follow
Gree’s requirement to add qualified lubricant of the specified trademark and ensure properness
of fill amount.
Step 14: Vacuum-pump.
After lubricant is added, keep on extracting air through a vacuum pump till the internal pressure reaches
the absolute pressure 0 kgf/cm
2
and the pressure gauge reads -1 kgf/cm
2
. This is to ensure that
moistures inside the pipeline system are completely vaporized.
Vacuum pumps of the specifications below are recommended:
Open all valves in order that the vacuum pump extracts air through all the valves, during which, connect
the units to a pressure gauge. When the internal pressure reaches 0 kgf/cm
2
and the pressure gauge
reads -1 kgf/cm
2
, keep on the extraction action for 0.5~1.0 hour more. Finally, turn off the rotary switch of
the gauge and close the pump. One hour later, if the pressure remains the same, fill refrigerant. If the
pressure increases to 0.1 kgf/cm
2
or higher, conduct leakage check again.
Connect the rubber hose
to the oil checking valve at
one end and put the other
end of the hose into the
glass for drawing lubricant
Extract air through all
valves. In the course of oil
fill, keep on the extraction
action