When the device is stopped more than once from the safety device, identify and correct the
cause before restarting.
Before resolving a special trouble shooting, this introduces the general troubles and troubleshooting methods.
When the chiller is not operating at all, the power, refrigerant, configuration and alarm setting of the chiller must
be checked. To check the power, the voltage connected to the terminal block within the power panel must be
checked. If there is no power, check the power supply and check whether the protective device is tripped.
When power is properly connected, the refrigerant pressure must be checked by the pressure gauge installed
on the chiller, and if the pressure is out of the range, check for any leakage using the soap test. If there is any
trouble with the PLC configuration or if the delay time is too long, the chiller will not Start to the Start time and
will be significantly delayed. Reset the setting to the default setting before starting the chiller. Lastly you must
check the alarm setting. You can check whether the alarm is turned ON through the HMI device. If the alarm is
turned ON, follow the alarm troubleshooting procedure.
Generally the compressor of the chiller operates by the cold water outlet temperature, compressor stop temper-
ature and the compressor restart temperature. But, the compressor can operate for a long period of time with-
out circulating. If the refrigerant is not sufficient, the chiller will operate continuously as it cannot be operated at
100% power. In this case, the leakage test must be done. When the magnetic contactor for the compressor
contacts mechanically, the chiller will continue to operate as the PLC cannot stop the compressor by the control
signal even when the compressor must be stopped. If there is no trouble with the refrigerant and compressor
contactor, it can be caused from the air inside the water circulation pipe that blocks the heat exchanger. If air
exists, the air must be purged. If there is uncondensed refrigerant in the pipe, it must be removed and
recharged. If the temperature is not recognized even after operating the cold water pump or if the compressor
does not operate due to the alarm issue, follow the alarm troubleshooting procedure.
Chiller Water-cooled Screw
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