Gree GMV-VQ680WM/C-X Service Manual page 229

Gree
6） If the vacuum degree cannot be maintained by two times of vacuums, you can confirm that
there is water inside the pipeline under the condition that there is no leakage. At this time, the
water should be removed by vacuum destruction. The specific method is: fill the pipeline with
0.05MPa nitrogen gas, vacuumize it for 2 hours, and keep vacuum for 1 hour. If it still can't reach
the vacuum degree of -0.1 MPa, repeat this operation until the water is drained.
7）After vacuuming, close the valve of the regulating valve and stop vacuuming for 1 hour.
Confirm that the pressure of the regulating valve has not risen.
8）After maintaining the vacuum, remove the charging pipe, disconnect the mode converter
and the power supply of indoor unit, and keep the cut-off valve on the mode exchange box pipeline
closed. After connecting the outdoor unit, please open the cut-off valve on the mode exchange box
pipeline and perform the vacuum pumping operation of the complete system according to 3.1.2.1.
GMV6 HR DC Inverter VRF Units Service Manual
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