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Troubleshooting
Electrical Control System
138
2.4.4.19. J8 malfunction
Malfunction
decision
conditions
An abnormal voltage rise or drop is detected by checking the
specified voltage detection circuit.
Supposed causes
Abnormal p
ower supply
Wiring
mistake
Faulty
bridge rectifier
Faulty IPM
board
AC power input voltage
protection
AC power input voltage
protection
J8 display
J8 display
Check whether the power
voltage is normal.
Check whether the power
voltage is normal.
Measure whether outdoor
terminal voltage is normal
?
Measure whether outdoor
terminal voltage is normal
?
Restart the unit when the power
supply gets normal
Restart the unit when the power
supply gets normal
No
Yes
No
Reconnect it well
Reconnect it well
Yes
Yes
No
Replace the IPM board, If the IPM board
and main board is in a board, replace the
outdoor main PCB
Replace the IPM board, If the IPM board
and main board is in a board, replace the
outdoor main PCB
Yes
Replace the PFC module(If has)
Replace the PFC module(If has)
No
Yes
Measure whether the voltage
between L and N is normal
?
Measure whether the voltage
between L and N is normal
?
Yes
Measure whether input voltage
of bridge rectifier is normal
?
Measure whether input voltage
of bridge rectifier is normal
?
Yes
No
No
Measure whether the voltage
between P and N is normal
refer to the
Appendix
3
?
Measure whether the voltage
between P and N is normal
refer to the
Appendix
3
?
Replace the bridge
rectifier
Replace the bridge
rectifier
No
Check whether
bridge rectifier is
normal
Check whether
bridge rectifier is
normal
Check the wiring of
reactor or inductance
Check the wiring of
reactor or inductance
Reconnect the
wiring
Reconnect the
wiring
No
Check whether reactor
or inductance is normal
Check whether reactor
or inductance is normal
Yes
Replace reactor or
inductance
Replace reactor or
inductance
No
Check the wiring of
power wires well or
correctly
Check the wiring of
power wires well or
correctly
Reconnect it well
Reconnect it well
Check the wiring of
L and N well or
correctly
Check the wiring of
L and N well or
correctly
Reconnect it well
Reconnect it well
Check the wiring of
bridge rectifier well
or correctly
Check the wiring of
bridge rectifier well
or correctly
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...