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Flooded type water cooled screw chiller (MIC)
MCAC-CTSM-2018-1
102
2. Troubleshooting
No.
Alarm
Trouble Description
Action
Reset Type
Possible Cause
1
Power Failure
Protection
Phase sequence relay
switches OFF
Compressor cannot work. The
compressor stop running
immediately
Reset it manually on the touch
screen
The power quality is poor due to phase inversion,
lacking phase or phase imbalance.
2
Compressor Motor
Protection
Compressor motor module
switches OFF
Compressor cannot work. The
compressor stop running
immediately
Power off the unit and
re-power up the electricity,
reset manually on the touch
screen
1 The power of motor is poor due to phase
inversion, lacking phase, over-voltage,
under-voltage
2. The motor overheats
3
Compressor Overload
Protection
Excessive current and
cumulated energy cause the
thermal relay to trip
The compressor will stop
running immediately
Reset it manually on the touch
screen
1,The compressor continues running in bad
conditions like over-current.
2,The setting value of thermal relay is too low
4
Contactor Protection
The coil of the contactor
does not perform suction
normally
The compressor will stop
running immediately
Reset manually on the touch
screen
1.The suction of the contactor is abnormal when
Y type switches to
△
type
2.The vibration during operations cause the
contact to loosen
5
Anti-freezing Protection
Anti-freezing switch OFF
The compressor will stop
running immediately
Reset it manually on the touch
screen
1,The chilled water flow falls sharply, the water
temperature too low
2,Anti-freezing switch is damaged or wiring
connection is abnormal
6
Water Flow Fault
The water flow switch
disconnects for more than
5s
1.The compressor cannot work.
The compressor stops running
immediately
;
2. Chilled water flow failure: The
chilled water pump stops
working after 30s delay; Cooling
water pump and cooling tower
shut down after 120s delay
3.Cooling water flow failure: The
cooling water pump and cooling
tower shut down after 30s delay;
chilled water pump stops
working after 180s delay.
Power off the unit and
re-power up the electricity,
reset manually on the touch
screen
1,The water pump fails and the water flow is too
small
2,Water flow switch fails or the wiring connection
is incorrect