Figure 4-2 Vacuumizing the single cooling system with installing low-temperature
component
(1) Liquid pipe needle valve
(2) Low pressure needle valve (2) High pressure needle valve
(4) Low pressure gauge
(5) High pressure gauge
(6) Vacuum pump
(7) Low pressure gauge
(8) High pressure gauge
Step 3 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 refrigerant or water in the cooling system.
Step 4 After 20 minutes, the pressure gauge pointer should be in the negative area and
the vacuum pump makes small noise. Close and open the pressure gauge
alternatively for several times. The position of the pressure gauge pointer and the
sound made by the vacuum pump do not change. Otherwise, the cooling system
may not be sealed properly.
NO TE
Charge the part refrigerant and then vacuumizing.
Step 5 Check that the time for vacuumization is 2 hours or longer after making sure that
the cooling system does not leak, the pressure displayed on the vacuum pump is
less than or equal to 60 Pa (or the pressure gauge is pointing to -76 cm Hg), and
the indication of sight glass is dry.
Step 6 Close the pressure gauge and vacuum pump. Preserve the pressure for 1 hour. The
pressure should not be restored over 80 Pa. If the pressure gauge is restored
obviously, locate the leakage and repair it.
----End
NetCol8000-A(050, 100) In-room Air Cooled Smart
Cooling Product
User Manual
4 Power-On Commissioning
Issue 12 (2020-10-28)
Copyright © Huawei Technologies Co., Ltd.
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