18
LEAKAGE TEST AND EVACUATION
ENGLISH
- When the desired vacuum is reached, close
the "Lo and Hi" knob of the manifold valve
and stop the vacuum pump.
Required time for evacuation when 4 CFM
vacuum pump is used
If tubing length is
less than 10 m(33 ft)
If tubing length is
longer than 10 m(33 ft)
30 min. or more
60 min. or more
0.8 Torr
- 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.
- 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 secure-
ly with an adjustable wrench. This process is
very important to prevent leakage from the sys-
tem.
Outdoor unit
Manifold valve
Vacuum pump
Open
Open
Pressure
gauge
Lo
Hi
Indoor unit
Finishing the Job
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 and Hi" 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.