LG AS-W096QGG1 Service Manual page 25

Soap water method
(1) Remove the caps from the 2-way and 3-way
valves.
(2) Remove the service-port cap from the 3-way valve.
(3) To open the 2-way valve turn the valve stem coun-
terclockwise approximately 90°, wait for about 2~3
sec, and close it.
(4) Apply a soap water or a liquid neutral detergent on
the indoor unit connection or outdoor unit connec-
tions by a soft brush to check for leakage of the
connecting points of the piping.
(5) If bubbles come out, the pipes have leakage.
3. Evacuation
• Connect the charge hose end described in the pre-
ceding steps to the vacuum pump to evacuate the
tubing and indoor unit.
Confirm the "Lo" knob of the manifold valve is
open. Then, run the vacuum pump.
The operation time for evacuation varies with tub-
ing length and capacity of the pump. The following
table shows the time required for evacuation.
Required time for evacuation when 30 gal/h vacuum pump is
If tubing length is less than 10m
(33 ft)
10 min. or more
• When the desired vacuum is reached, close the
"Lo" knob of the manifold valve and stop the vacu-
um pump.
4. Finishing the job
• With a service valve wrench, turn the valve stem of
liquid side valve counter-clockwise to fully open
the valve.
• Turn the valve stem of gas side valve counter-
clockwise to fully open the valve.
• Loosen the charge hose connected to the gas side
service port slightly to release the pressure, then
remove the hose.
• Replace the flare nut and its bonnet on the gas
side service port and fasten the flare nut securely
with an adjustable wrench. This process is very
important to prevent leakage from the system.
• Replace the valve caps at both gas and liquid side
service valves and fasten them tight.
This completes air purging with a vacuum pump.
The air conditioner is now ready to test run.
used
if tubing length is longer than 10m
(33 ft)
15 min. or more
3-way valve
(Close)
2-way valve
(Open)
Hexagonal wrench
Outdoor unit
Manifold valve
Pressure
Lo
gauge
Open
Vacuum pump
Installation
Gas side
Liquid side
Cap
Indoor unit
Hi
Close
Service Manual 25