C. Evacuation
• Connect the charge hose end described in the preced-
ing 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 tubing
length and capacity of the pump. The following table
shows the time required for evacuation.
• When the desired vacuum is reached, close the "Lo"
knob of the manifold valve and stop the vacuum pump.
D. Finishing the job
1) With a service valve wrench, turn the valve stem of liq-
uid side valve counter-clockwise to fully open the
valve.
2) Turn the valve stem of gas side valve counter-clock-
wise to fully open the valve.
3) Loosen the charge hose connected to the gas side
service port slightly to release the pressure, then
remove the hose.
4) 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.
5) Replace the service valve caps at both the gas and
the liquid side and fasten them tight.
This completes air purging with a vacuum pump.
The air conditioner is now ready to test run.
(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 counter-
clockwise 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 connections by a
soft brush to check for leakage of the connecting points
of the piping.
(5) If bubbles come out, the pipes have leakage.
Soap water method