Service and Parts Manual (2019, 2020, 2021, 2022)

108 PB
TROUBLESHOOTING
Indoor Unit Fault Codes
Fault
code
Fault description
Possible reason s f or bnormality
How to eal ith
Re marks
74
Indoor EEPROM
Data 2 fault
EE in MCU fails, the unit
can run, but the function
user has set is ineffective.
Replace EE data in MCU.
81
Indoor ambient
Temperature
Sensor Fault
1. The cabl e of the room
temperature sensor is connect ed
loose ly;
2. The room temperature sensor
fails;
3. The sampling circuit is abnormal .
83
1. Reconnect the cable of the
room temperature sensor;
2. Replace the room temperature
sensor;
3. Replace the indoor control
board.
E vaporator Middle
Temperature
Sensor Fault
1.The cabl e of the coil temperature
sensor of the evaporator fails;
2.The coil temperatur e sensor of
the evaporator fails;
3.The sampli ng circuit is abnormal .
FE
(254)
1. Reconnect the cable of the
coil temperature sensor of the
evaporator;
2. Replace the coil
temperature sensor of the
evaporator;
3. Replace the indoor
control board.
C ommunication
between main
control boar d &
Wired controller
Fault (display on
wired controller)
1.
2.
Reconnect the wiring between
the wired controller to the
indoor control board;
Replac e the wiring between
the wired controller to the
indoor control board;
1. The wired controller and the
indoor control boar d are
connect ed loose ly.
2. The sequenc e of the wiring
between the wired controller
to the indoor contro
l board is
wrong;
3. The wiring betwee n the
wired controller to the indoor
control board fails;
4. The wired controller is fails;
5. The indoor control board
is abnormal .
ER
3. Replac e the wiring between
the wired controller to the
indoor control board;
4. Replac e the wired controller;
5. Replac e the indoor control
boa rd.
C ommunication
between main
control board
& display board
Fault (displays on
display board)
1.The wiring betwee n the display
board to the indoor control
board is connect ed loose ly;
2.The sequenc e of the wiring
between the display board to the
indoor control boar d is wrong;
3.The wiring between the display
board to the indoor control
board fails;
4.The display boar d fails;
5.The indoor control boar d fails.
1. Reconnect the wiring
between the display board
to the indoor control board;
2. Replac e the wiring between
the display boar d to the
indoor control board;
3. Replac e the wiring between
the display boar d to the
indoor control board;
4. Replac e the display board;
5. Replac e the indoor control
board.