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7. Air Purging of the Pipes and Indoor Unit
The air which contains moisture remaining in the refrigeration cycle may cause a malfunction on the compressor.
1. Confirm that both the liquid side valve and the gas side valve are set to the closed position.
2. After connecting the piping, check the joints for gas leakage with gas leak detector.
3. Remove the service port nut, and connect the gauge manifold and the vacuum pump to the service port by the
charge hose.
4. Vacuum the indoor unit and the connecting pipes until the pressure in them lowers to below -76cmHg.
5. Remove the valve stem nuts, and fully open the stems of the 2-way and 3-way valves with a hexagon wrench.
6. Tighten the valve stem nuts of the 2-way valve and 3-way valve.
7. Disconnect the charge hose and fit the nut to the service port.
(Tightening torque: 1.8kg.m)
Indoor unit
Outdoor unit
Liquid side
CLOSE
OPEN
Vaccum pump
Gas side
Closed
Closed
2-way valve/
3-way valve
3-way
valve