Leakage test and Evacuation
1. 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 and Hi" 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.
2. When the desired vacuum is reached, close the "Lo
and Hi" knob of the manifold valve and stop the
vacuum pump.
Finishing the job
1. With a service valve wrench, turn the valve stem of
liquid side valve counter-clockwise to fully open the
valve.
2. Turn the valve stem of gas side valve counter-
clockwise 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 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.
Indoor unit
Outdoor unit
Lo
Hi
Manifold valve
Vacuum pump
Open
Open
Pressure
gauge
Gas pipe
Evacuation
Required time for evacuation when 30 gal/h
vacuum pump is used
30 min. or more
60 min. or more
0.07 kPa or less
If tubing length is less
than 10 m(33 ft)
If tubing length is longer
than 10 m(33 ft)
18
Air Conditioner
