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Troubleshooting
Electrical Control System
125
F0 displayed
F0 displayed
Current protection of compressor
Current protection of compressor
Was the protection activated
in standby?
Was the protection activated
in standby?
Yes
Yes
Is the current normal
?
Is the current normal
?
Yes
No
Replace the outdoor main PCB
Replace the outdoor main PCB
Is the power voltage is
normal?
Is the power voltage is
normal?
Is outdoor terminal voltage
normal
?
Is outdoor terminal voltage
normal
?
Restart the unit when the power
supply returns to normal
Restart the unit when the power
supply returns to normal
No
Yes
No
Reconnect the
power wiring
Reconnect the
power wiring
Yes
Is the voltage between L and
N is normal
?
Is the voltage between L and
N is normal
?
Yes
Is the input voltage of the
bridge rectifier is normal
?
Is the input voltage of the
bridge rectifier is normal
?
No
No
Is the power wiring
wired correctly?
Is the power wiring
wired correctly?
Reconnect L and N
Reconnect L and N
Are L and N wired
properly?
Are L and N wired
properly?
Reconnect the
bridge rectifier
Reconnect the
bridge rectifier
Is the bridge
rectifier wired
properly?
Is the bridge
rectifier wired
properly?
No
No
Yes
Replace the PFC module (if this has not
been done already)
Replace the PFC module (if this has not
been done already)
No
Is the voltage between P and
N normal
refer according to
Appendix
3
?
Is the voltage between P and
N normal
refer according to
Appendix
3
?
Replace the bridge
rectifier
Replace the bridge
rectifier
No
Is the bridge rectifier
functioning normally?
Is the bridge rectifier
functioning normally?
Is the wiring of the
reactor or inductance
properly wired?
Is the wiring of the
reactor or inductance
properly wired?
Reconnect the
wiring
Reconnect the
wiring
No
Are the reactor and
inductance functioning
normally
Are the reactor and
inductance functioning
normally
Yes
Replace reactor or
inductance
Replace reactor or
inductance
No
Is the outdoor ambient
temperature is higher than
50
℃
?
Is the outdoor ambient
temperature is higher than
50
℃
?
No
Stop the unit
Stop the unit
Yes
Is the outdoor unit
ventilation functioning
properly?
Is the outdoor unit
ventilation functioning
properly?
Yes
Ensure that the outdoor unit
ventilate is working properly
Ensure that the outdoor unit
ventilate is working properly
Is the heat exchanger dirty?
Is the heat exchanger dirty?
No
Clean the heat exchanger
Clean the heat exchanger
Yes
Check whether the refrigerant
system is running normally
Check whether the refrigerant
system is running normally
Replace outdoor main
board. Does a problem still
exist?
Replace outdoor main
board. Does a problem still
exist?
No
No
Is the outdoor fan running
properly?
Is the outdoor fan running
properly?
Refer to the solution to the
malfunction of fan speed being out
of control. Find the cause and
resolve the issue
Refer to the solution to the
malfunction of fan speed being out
of control. Find the cause and
resolve the issue
No
Yes
No
Yes
Yes
Is system pressure too high?
Is system pressure too high?
Recycle the overcharged
refrigerant
Recycle the overcharged
refrigerant
Yes
Summary of Contents for 38QUS012D8S
Page 1: ...Contents i Energy Related Products SUPER DC INVERTER SERIES Service Manual...
Page 13: ...Service Space Indoor Units 11 3 Service Space 1000mm 1000mm 1000mm 1000m m Chart 3...
Page 16: ...Air Velocity Distributions Reference Data Indoor Units 14 30 42K Cooling Heating...
Page 17: ...Air Velocity Distributions Reference Data Indoor Units 15 48 55K Cooling Heating...
Page 22: ...Field Wiring Indoor Units 20 10 Field Wiring 42QTD018R8S 42QTD024R8S 42QTD036R8S...
Page 23: ...Field Wiring Indoor Units 21 42QTD048R8S 42QTD060R8S...
Page 29: ...Features Indoor Units 27...
Page 46: ...Service Space Indoor Units 44 3 Service Space...
Page 61: ...Wiring Diagrams Outdoor Units 59 3 Wiring Diagrams 38QUS018R8S...
Page 62: ...Wiring Diagrams Outdoor Units 60 38QUS024R8S...
Page 63: ...Wiring Diagrams Outdoor Units 61 38QUS036R8S...
Page 64: ...Wiring Diagrams Outdoor Units 62 38QUS036R8T...
Page 65: ...Wiring Diagrams Outdoor Units 63 38QUS048R8T 38QUS060R8T...
Page 87: ...Refrigerant pipe installation Installation 85...