22
Evacuation
- Connect the charge hose end described in
the preceding steps to the vacuum pump to
evacuate the tubing and indoor unit.
Confirm the "Lo" knob of the pressure Gauge
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.
2-way valve
(Close)
3-way valve
(Close)
Required time for evacuation when 30 gal/h
vacuum pump is used
If tubing length is
less than 10m (33 ft)
10 min. or more
- When the desired vacuum is reached, close
the knob of the 3-way valve and stop the
vacuum pump.
Liquid side
Gas side
Cap
If tubing length is
longer than 10m (33
ft)
15 min. or more
Finishing the Job
- With a service valve wrench, turn the valve of
liquid side counter-clockwise to fully open the
valve
- Turn the valve of gas side 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.
Outdoor unit
Manifold valve
Pressure
Lo Hi
gauge
Open
Vacuum pump
- Replace the valve caps at both gas and liquid
side service valves and fasten them tight.
This completes air purging with a vacuum pump.
- Replace the pipe cover to the outdoor unit by
one screw
Now the air conditioner is ready for test run.
Indoor unit
Close