NetCol5000-A020 Air Cooled In-row Precision Air
Conditioner
User Manual
5 System Operation and Maintenance
Issue 01 (2014-06-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
76
Item
Operations
Troubleshooting
Result
within the normal range
(24 V AC±10%).
Cables
Check that the power
cables and the cables
connecting the indoor unit
and outdoor unit are not
aging.
Replace cables if necessary.
T/H sensors
Check that the
temperature and humidity
readings are correct as
measured.
Calibrated by a high-precision
temperature and humidity meter.
Water
sensor
Check that the water leak
sensor (optional) is
securely installed and its
probe is appropriately
located.
Keep the water sensor far away
from drain traps or floor drains in
the equipment room and at least 0.5
m from the air conditioner.
5.3 Other Cooling System Components
To ensure that the cooling system works properly, inspect it at least once a year. It is
recommended that you inspect the cooling system at shorter intervals in adverse working
environments.
Before measuring the temperature and pressure of discharge and suction, power off the device.
Deploy thermocouples on the discharge and suction pipes, connect pressure gauges to the
high-pressure and low-pressure needle valves, and power on the device. Wait for 30 minutes
and measure the temperature and pressure of discharge and suction.
Discharge Pressure
Check the discharge pressure. Discharge pressure depends on load conditions and condenser
efficiency. When discharge pressure reaches the high-pressure switch threshold, the switch
reacts to stop the compressor. High-voltage switching action value is 4.25 MPa, recovery
pressure value is 3.60 MPa.
Suction Pressure
Check the suction pressure. When suction pressure is below the low-pressure switch threshold,
the switch reacts to stop the compressor. Excessive suction pressure would deteriorate the
cooling performance of refrigerant on the compressor motor and damage the compressor.
Suction pressure should range from 0.7 MPa to 1.2 MPa in the rated working environment