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TROUBLESHOOTING
Wiring Connection Failure
Check circuit by tester
Repair the wiring
connection
Printed Circuit Board
Failure
Printed Circuit Board
Failure
Check circuit by tester Check
Printed Circuit Board by self-
checking function
Replace Printed Circuit
Board
Remote Control Switch Failure
Operative by the unit side
Replace remote
control switch.
Coil Broken
Check circuit by tester
Pump runs,
but neither
fan nor
compressor
run.
Fan Magnetic Contactor
Failure (Cooling
Operation)
Contact Point Failure
Measure the voltage between
contact points of magnetic
contactor.
Replace magnetic
contactor.
Fan Motor Failure
Measure the interphase
resistance
Replace fan motor
Pump and
compressor
run, but fan
does not run
Wiring Connection Failure
Printed Circuit Board
Failure
Check circuit by tester
Repair the wiring
connection.
Printed Circuit Board
Failure
Thermistor Malfunction
Measure the thermistor resistance
Replace thermistor
Coil Breaking
Check circuit by tester
Compressor Magnetic
Contactor Failure
Contact points Failure
Measure the voltage between
contact points of electromagnetic
contactor
Replace magnetic
contactor
Thermostat is activated. (Thermo-Off)
Change water temperature or
change the setting temperature.
It is not failure
Compressor Motor Failure
Measure the interphase
resistance
Pump and
fan run but
compressor
does not run.
Compressor Failure
Beat noise from compressor
Replace compressor
Voltage at starting up is low.
Measure the voltage
Consult with electric
power company
Excessive dust in air side heat
exchanger
Inlet or outlet of air side heat
exchanger is clogged
Remove it.
Shortage of Service Space for
Chiller Unit
Secure the service
space
Insufficient air in air side
heat exchanger
Reverse Rotation of Fan Motor
Change wiring for fan
motor
Air Short Circuits in Chiller Unit
Remove short-circuits
Air temperature through air
side heat exchanger is
excessively high
Another heat source around
chiller unit
Remove heat source
Refrigerant excessive
charge
Check cycle temperature.
Charge correct
quantity of refrigerant
Non-condensable gas in
the refrigerant cycle
Turn off the unit and check the
relation between water
temperature and pressure.
Charge refrigerant
again after the
evacuation
High pressure pipe
clogging
Check clogging
Expansion Valve clogging
Check Valve (Air side heat
exchanger side) clogging
Check clogging
Remove clogging, or
replace check valve
Strainer Clogging
Check the difference of
temperature before and after of
strainer.
Replace or clean the
strainer
Discharge pressure is
excessively high, so that
high pressure switch
activates.
(C1-H1)~ (C6-H6)
Chilled water inlet
temperature of Water side
heat exchanger is
excessively high
Confirm if it is within the working
range
Check the status of
heat load in detail and
take a countermeasure
Unit stops
during
cooling
operation
Discharge gas control is
activated
Suction gas temperature is
excessively high
(Excessively super heat)
Gas leakage or refrigerant
shortage
Charge correct
quantity of refrigerant
after checking gas
leakage
