LG Multi F A2UW14GFA0 Engineering Product Data Book page 325

2. Guideline for each installation process
2.7.2 Evacuation
① Connect the manifold 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.
② When the desired vacuum is reached, close the "Lo" knob of the manifold valve and stop the vacuum pump.
Gas Pipe Gas Pipe Gas Pipe
Manifold gauge
Outdoor unit
Manifold valve
Pressure
Lo Hi
gauge
Open
Vacuum pump
CAUTION
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. Loose 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 fasten the flare nut securely with an adjustable wrench. This process is very important to pre-
vent 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 for test run.
Liquid Pipe Liquid Pipe Liquid Pipe
Close
Outdoor unit
Manifold valve
Digital vacuum
Lo Hi
gage
Open Open
Vacuum pump
Heat pump 50Hz/R410A
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