Hisense AS-07UR4SYDDB15, Service Manual

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4-­‐4. Air Purging and Leakage Test
1. Connect charging hose of manifold valve to charge end of low pressure valve (both high/low
pressure valves must be tightly shut).
2. Connect joint of charging hose to vacuum pump.
3. Fully open the handle of Lo manifold valve.
4. Open the vacuum pump to evacuate. At the beginning, slightly loosen joint nut of low pressure
valve to check if there is air coming inside. (If noise of vacuum pump has been changed, the reading
of multimeter is 0) Then tighten the nut.
5. Keep evacuating for more than 15mins and make sure the reading of multi-meter is -1.0 X105 pa
(-76cmHg).
6. Check the vacuum with the gage manifold valve, then close the gage manifold valve, and stop the
vacuum pump.
7. Leave it for one or two minutes. Make sure the pointer of the gage manifold valve remains in the
same position.
8. Remove the gage manifold valve quickly from the service port of the stop valve.
After refrigerant pipes are connected and evacuated, fully open all stop valves on gas and liquid pipe
sides.
9. Opening without fully opening lowers the performance and cause dangerous.
10. Tighten the cap to the service port to obtain the initial status.
11. Retighten the cap
12. Leak test