Air Purging and Evacuation
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 tubing length and capacity of the pump. The following table shows the time required for evacuation.
Required time for evacuation when 4 cfm vacuum
pump is used
If tubing length is less | If tubing length is longer |
than 10m (33 ft) | than 10m (33 ft) |
|
|
10 min. or more | 15 min. or more |
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 liquid side valve
2.Turn the valve stem of gas side 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.
|
| Indoor unit |
| Outdoor unit | |
| Manifold valve | |
Pressure | Hi | |
gauge | Lo | |
|
| |
| Open | Close |
| Vacuum pump | |
This completes air purging with a vacuum pump.
The air conditioner is now ready for test running.
NOTICE
:Repeat evacuation procedure for each indoor unit.
26Room Air Conditioner