Troubleshooting
55
Symptom
Possible Cause
Items to be Checked or Handling Method
The contactor
is closed, the
compressor is
not running
MCB tripped
Check the line voltage after checking the circuit
breaker and contactor
Compressor built-in protector
disconnected
Check whether the compressor coil is open. If open,
wait for the coil to cool down and reset automatically
Detect exhaust air temperature sensor
Is there an alarm for low exhaust air superheat/high
temperature
Detect low pressure sensor
Check whether there is a low voltage alarm in the
history alarm
Low pressure sensor failure (11 minutes
after shutdown)
Check whether the low-pressure sensor wiring of the
system is intact and the reading is normal
Motor drive failure (11 minutes after
shutdown)
Check whether the wiring is normal, whether the
current is too large, check whether the ventilation of
the motor drive is normal
Motor drive communication failure (11
minutes after shutdown)
Check whether the wiring of the RS458
communication line of the motor drive is intact, then
re-power on and reset or the panel will eliminate this
fault alarm
The compressor
stops after
running for 5
minutes
Refrigerant leak, low pressure detection
is too low/abnormal
• Check the suction pressure;
• Check the circuit where the low-pressure sensor is
located;
• Check whether the reading of the low pressure
sensor and the actual pressure are within ±0.3bar
(the value of the high and low pressure sensor can
be read in the maintenance menu/troubleshoot
setting and displayed as absolute pressure)
High pressure
protection
Dirty condenser
Inlet water temperature is too high or
water flow is too small (water cooling)
Clean the condenser or change the plate type
exchanger;
Check the water system (water cooling)
Condenser equipment does not operate
Air cooling system, check the condenser fan;
Water cooling system, check the water system
Excessive refrigerant charge
Check whether the subcooling is too high
Improper adjustment of electric ball
valve (water cooling)
• It is necessary to check whether the reading of
the high pressure sensor and the actual value
are within the range of ±0.6bar (the value of the
high and low pressure sensor can be read in the
maintenance menu/troubleshoot setting and
displayed as absolute pressure);
• It is necessary to check whether the electric ball
valve of the plate type heat exchanger is operating
normally
Low exhaust
pressure
The water flow is too large or the inlet
water temperature is too low (water
cooling)
Check the water system
Refrigerant leak
Check for leaks and repair and add refrigerant
