Mitsubishi Heavy Industries FDT71VNXVD Service Manual page 27

(ii) Outdoor unit
Remote controller Indoor control PCB Outdoor control PCB Outdoor inventer PCB
Green
Error code Red LED Red LED
Red LED
LED (1)
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps
Stays OFF 1 time flash
flashing
Keeps 5 times
Stays OFF
flashing flash
Note (1) * mark in the Description of trouble means that, in ordinary diagnosis, it cannot identify the cause definitely, and, if the trouble is repaired by replacing the part, it
is judged consequently that the replaced part was defective.
(iii) Optional controller in-use
Indoor unit control PCB
Error code Red LED Red LED Green LED
Keeps flashing Stays OFF Keeps flashing
Location of trouble
Green Yellow
LED (1) LED
Power supply wires
Keeps
flashing
Outdoor control PCB
Installation or operating
condition
Keeps
Outdoor heat exchanger
flashing
temperature thermistor
Outdoor control PCB
Installation or operating
condition
Discharge pipe
Keeps
temperature thermistor
flashing
Outdoor control PCB
Keeps
flashing
Outdoor heat exchanger
temperature thermistor
Keeps
flashing
Outdoor control PCB
Outdoor air temperature
thermistor
Keeps
flashing
Outdoor control PCB
Discharge pipe
temperature thermistor
Keeps
flashing
Outdoor control PCB
Installation or operating
Keeps
condition
flashing
Outdoor control PCB
2 times flash
Keeps Inverter PCB or radiator
or
flashing fin
6 times flash
Outdoor control PCB
1 time flash
compressor
Keeps
or
flashing
Installation or operating
5 times flash
condition
Outdoor control PCB
Keeps Keeps
flashing flashing
Inverter PCB
Keeps Inverter PCB
7 times flash
flashing activefilter
Outdoor fan motor
Keeps
flashing
Outdoor control PCB
Installation or operating
Keeps
condition
flashing
Keeps
Low pressure sensor
flashing
Outdoor control PCB
2 times flash
Keeps
or Inverter PCB
flashing
6 times flash
Suction pipe
temperature thermistor
Keeps
flashing
Outdoor control PCB
Low pressure sensor
Keeps
Keeps
flashing
flashing
Outdoor control PCB
Operation status
Keeps
flashing
Installation status
Stays OFF or
Keeps Compressor inverter
4 times
PCB
flashing
flash
Outdoor unit control PCB
Red LED Green LED
Stays OFF Keeps flashing • Communication error (Defective communication circuit on the main unit of SC-SL2N-E or SC-SL3N-E) ete.
- 27
Description of trouble
• Outdoor unit power supply L3-phase interruption, defective noise filter
(3-phase model only)
*• Defective outdoor control PCB (Defective power supply input circuit)?
(3-phase model only)
• Higher outdoor heat exchanger temperature
• Defective outdoor heat exchanger temperature thermistor
*• Defective outdoor control PCB (Defective temperature thermistor input
circuit)?
• Higher discharge temperature
• Defective discharge pipe temperature thermistor
*• Defective outdoor control PCB (Defective temperature thermistor input
circuit)?
• Defective outdoor heat exchanger temperature thermistor, broken wire or poor
connector connection
*• Defective outdoor control PCB (Defective temperature thermistor input
circuit)?
• Defective Outdoor air temperature thermistor, broken wire or poor connector
connection
*• Defective outdoor control PCB (Defective temperature thermistor input
circuit)?
• Defective discharge pipe temperature thermistor, broken wire or poor
connector connection
*• Defective outdoor control PCB (Defective temperature thermistor input
circuit)?
• Rising high pressure (Operation of 63H1) • Service valve closing operation
*• Defective outdoor control PCB (Defective 63H input circuit)?
• Power transistor overheat (Single phase modelonly)
• Current cut (Anomalous compressor over-current)
• Service valve closing operation
• Anomalous outdoor control PCB communication
• Anomalous inverter PCB communication
• Defective outdoor inverter PCB (Model FDC 71)
Defective active filter of control.
• Anomalous outdoor fan motor
*• Defective outdoor control PCB (Defective motor input circuit)?
• Low pressure error • Service valve closing operation
• Anomalous low pressure, broken wire of low pressure sensor or poor
connector connection
*• Defective outdoor control PCB (Defective sensor input circuit)?
• Anomalous inverter PCB
• Defective suction pipe temperature thermistor, broken wire or poor connector
connection
*• Defective outdoor PCB (Defective thermistor input circuit)?
• Defective low pressure sensor
• Defective outdoor control PCB (Defective sensor input circuit)?
• Shortage in refrigerant quantity
• Service valve closing operation
• Anomalous compressor startup
Description of trouble
-
'10 • PAC-SM-137A
Reference
Repair method
page
Repair
81
Replacement of PCB
Repair
Replacement of
82
temperature thermistor
Replacement of PCB
Repair
Replacement, repair of
83
temperature thermistor
Replacement of PCB
Replacement, repair of
temperature thermistor
84
Replacement of PCB
Replacement, repair of
temperature thermistor
85
Replacement of PCB
Replacement, repair of
temperature thermistor
86
Replacement of PCB
Repair
87
Replacement of PCB
Replacement of PCB
88
or Repair
Replacement of PCB
89 •90
Repair
Service valve opening
check
91
Replacement of PCB
Replacement 92
Replacement, repair
93
Replacement of PCB
Repair
Replacement, repair of
94,95
sensor
Replacement of control
PCB
Replacement of PCB 96
Replacement, repair of
temperature thermistor
97
Replacement of control
PCB
Replacement of sensor
98
Replacement of control
PCB
Repair
99
Service valve opening
check
Replacement 100
Repair method
Replacement