n Operating Procedure
Do not operate the contactor manually. It can cause severe damage to the machine.
Follow the below procedure.
• Check whether the air processing equipment that supplies water to the chiller or other devices that operate the
water load. Start of the water load equipment can be delayed when the temperature of the chilled water is too
• When the Auto control does not work in the chiller, check whether the water circulation pump is operating.
• Check and audit all the fuses. All the fuses on the power and control panel must be installed in the correct
• Check and audit the condition of the touch screen of PLC and HMI. HMI will display the LG logo as it is turned
on and then the normal screen must be displayed afterwards.
• Check and audit the voltage monitoring meter inside the power panel. The voltage monitoring meter must not
display any error code.
• Use the HMI device to check the cold water outlet temperature and coolant water outlet temperature setting.
• Set the start menu of the HMI device to start the system.
• After operating the machine for a short time, check the oil amount inside each compressor and check whether
the coolant liquid meter is flashing.
• While the device is operating, the coolant water temperature must be within 20°C~40°C.
• To appropriately control the temperature, the water circulation flux must be within the permitted range.
After the above installation, operate the chiller to check whether all the functions are operating correctly.
Check whether the setting point of the cold water outlet and coolant water outlet are the same.
Also through HMI device, check whether all the Sensors have an effective value.
PLC detects the temperature using the 5NTC Thermistors, and the thermistor detects the compressor discharge
temperature, coolant water inlet temperature, coolant water outlet temperature, cold water inlet temperature and
cold water outlet temperature.
Chiller Water-cooled Screw
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