LG LAN091CNP, LAU091CNP, LAN121CNP Service Manual page 57

1) Re-air purging
(Re-installation)
Gas cylinder
Refrigerant
• Procedure
(1) Confirm that both the liquid side valve and the
gas side valve are set to the closed position.
(2) Connect the charge set and a gas cylinder to
the service port of the Gas side valve.
– Leave the valve on the gas cylinder closed.
(3) Air purging.
– Open the valves on the gas cylinder and the
charge set. Purge the air by loosening the flare
nut on the liquid side valve approximately 45°
for 3 seconds then closing it for 1 minute;
repeat 3 times.
– After purging the air, use a torque wrench to
tighten the flare nut on liquid side valve.
(4) Check for gas leakage.
– Check the flare connections for gas leakage.
(5) Discharge the refrigerant.
– Close the valve on the gas cylinder and dis-
charge the refrigerant until the gauge indicates
3 to 5 kg/cm 2 g.
Indoor unit
Lo
OPEN
Liquid side
Closed
3-Way
valve
Gas side
Closed
3-Way
valve
CLOSE
(6) Disconnect the charge set and the gas cylin-
der, and set the Liquid side and Gas side
valves to the open position.
– Be sure to use a hexagonal wrench to operate
the valve stems.
(7) Mount the valve stem nuts and the service
port nut.
– Use torque wrench to tighten the service port
nut to a torque of 1.8 kg.m.
– Be sure to check for gas leakage.
* CAUTION:
Do not leak the gas in the air during Air
Purging.
Troubleshooting Guide
Outdoor unit
Service Manual 57