GE AS0CD09 Series, Technical Service Manual

Page: 35 / 72

33
Evacuation
1. 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 manifold valve is open.
Then run the vacuum pump.
The operation time for evacuation varies with the tubing
length and capacity of the pump. The following table shows
the amount of time for evacuation. Allow the pump to
operate until the system has been evacuated down to 300
micros. Allow the pump to continue running for an addi-
tional 15 minutes. Turn off the pump and leave the connec-
tions secured to the two service valves. After 5 minutes, if
the system fails to hold 500 microns or less, check all
connections for tight fit and repeat the evacuation proce-
dure.
2. When the desired vacuum is reached, close the “LO”
knob of the manifold valve and stop the vacuum pump.
Finishing the job
1. With a service valve wrench, turn the valve stem of the
liquid side valve counterclockwise to fully open the valve.
2. Turn the valve stem of gas side valve counterclockwise
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 gas from leaking from the system.
5. Replace the valve caps at both gas and liquid side
service valves and fasten them securely.
This completes air purging with a vacuum pump. The air
conditioner is now ready to test run.