damage due to liquid strike. An excessive overheat degree would affect system
performance.
NO TE
The superheat degree should range from 6°C to 13°C.
Determine the suction superheat degree as follows:
1. Measure the pipe wall temperature at the sensing bulb.
2. Measure the pressure at the needle value for the suction pipe and find out the
saturation temperature by using the measured pressure as the reference
pressure inside the evaporator.
3. Determine the difference between the temperature at the sensing bulb and
the found temperature as the suction superheat degree.
Thermostatic Expansion Valve
The thermostatic expansion valve adjusts the suction superheat degree. Perform
maintenance on the thermostatic expansion valve as follows:
1. Check that the sensing bulb is securely installed.
2. Check that no fracture exists on the sensing bulb and capillary tubes.
3. Check that no crack exists at the soldering points of the equalizer pipe.
It is recommended that you do not adjust the thermostatic expansion valve onsite
because it has been adjusted before delivery. If the superheat degree is too low or
high, adjust the thermostatic expansion value as follows at your deliberation or
after consulting Huawei technical support:
1. Unscrew the valve bonnet at the bottom.
2. Rotate the adjustment screw rod clockwise to increase the superheat degree.
3. Rotate the adjustment screw rod counter-clockwise to decrease the superheat
degree.
NO TICE
Rotate the adjustment screw rod within one circle each time. About 30 minutes
are required to achieve a new balance.
Sight Glass
Maintain the sight glass as follows:
1. Check the sight glass. If the ground color is yellow, the cooling system
contains excessive water and requires maintenance.
2. If you find air bubbles with the sight glass, the cooling system lacks
refrigerant. Adjust the expansion valve or fill in refrigerant.
Refrigerant Pipe
Maintain the refrigerant pipe as follows:
NetCol8000-A(050, 100) In-room Air Cooled Smart
Cooling Product
User Manual
7 System Operation and Maintenance
Issue 12 (2020-10-28)
Copyright © Huawei Technologies Co., Ltd.
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