Figure 4-77 Vacuumization
(1) Vacuum pump
(2) Pressure gauge
(3) Gas pipe needle
valve
(4) Liquid pipe needle
valve
Step 2 In the beginning, the vacuum pump makes loud noises and exhausts white smoke
from the exhaust vent. After 10 minutes, if it still exhausts white smoke, observe it
for another 10 minutes because the cooling system may not be sealed properly or
there may be too much water in the cooling system.
Step 3 After 20 minutes, the pressure gauge pointer should be in the negative area and
the vacuum pump makes small noises. Close and open the pressure gauge
alternatively for several times. The position of the pressure gauge pointer and the
noises made by the vacuum pump do not change. Otherwise, the cooling system
may not be sealed properly.
Step 4 Check that the time for pumping out the air is 80 minutes or longer after making
sure that the cooling system does not leak, and that the pressure displayed on the
vacuum pump is less than or equal to 60 Pa (absolute pressure). When the
pressure stops dropping, pump for another 10 minutes.
Step 5 After vacuumization, close all valves of the pressure gauge and the vacuum pump
without disconnecting it. Preserve the pressure for 10 minutes, and verify that the
absolute pressure of the cooling system is not greater than 90 Pa.
NO TE
If the pressure gauge cannot display 60 Pa (absolute pressure), perform vacuum pumping
so that the pressure gauge stays at the smallest scale and preserve the pressure for 1 hour.
Then, check whether the pressure displayed on the gauge has an obvious increase.
Step 6 After making sure that the pressure gauge has no obvious increase, open the stop
valves for the gas pipe and liquid pipe of the outdoor unit.
FusionModule800 Smart Small Data Center
User Manual
4 Installation Guide
Issue 01 (2021-02-05)
Copyright © Huawei Technologies Co., Ltd.
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