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Installation and Maintenance
Service Manual
9. Maintenance
9.1 Error Code
No. Malfunction
Name
Display Method of Indoor Unit
A/C Status
Possible Causes(For specific maintenance
method, please refer to the following procedure of
troubleshooting)
Error
Code
Indicator lamp (Only for
the unit with indictor;
during blinking, ON for
0.5S and OFF for 0.5S)
Operation
Lamp
COOL
Lamp
HEAT
Lamp
1
Indoor ambient
temperature
sensor is
open/short-
circuited
F1
Blinks
once
every
3s
The unit will stop operation
as it reaches the temperature
point. During cooling and
drying operation, except IDU
fan motor operates, other
loads stop operation; During
heating operation, the system
stops operation.
1. The wiring terminal between indoor ambient
temperature sensor and main board is loosened or
poorly contacted;
2. There’s short circuit due to trip-over of the parts
on controller;
3. Indoor ambient temperature sensor is damaged
(Please check it by referring to the resistance table
for temperature sensor)
4. Main board is broken.
2
Indoor
evaporator
temperature
sensor is
open/short-
circuited
F2
Blinks
twice
every
3s
The unit will stop
operation as it reaches
the temperature point.
During cooling and drying
operation, except IDU fan
operates, other loads stop
operation; During heating
operation, the complete unit
stops operation.
1. The wiring terminal between indoor evaporator
temperature sensor and main board is loosened or
poorly contacted;
2. There’s short circuit due to the trip-over of the
parts on controller;
3. Indoor evaporator temperature sensor is damaged
(Please check it by referring to the resistance table
for temperature sensor)
4. Main board is broken.
3
Blocked
protection of
IDU fan motor
H6
Blinks
11 times
every 3s
IDU fan, ODU fan,
compressor and electric
heat tube stop operation.
Horizontal louver stops at the
current position.
1. The feedback terminal of PG motor is not
connected tightly.
2. The control terminal of PG motor is not connected
tightly.
3. Fan blade rotates unsmoothly.
4. Malfunction of motor
5. Main board is broken.
4
Malfunction
protection of
jumper cap
C5
Blinks 15
times
every 3s
Operation of remote
controller or control panel is
available, but the unit won’t
act.
1. There’s not jumper cap on the main board.
2. Jumper cap is not inserted properly and tightly.
3. Jumper cap is damaged.
4. Controller is damaged.
5
Overcurrent
protection
E5
Blinks 5
times
every 3s
During cooling and drying
operation, except IDU fan
motor operates, other loads
stop operation; During
heating operation, the system
stops operation.
1. Unstable supply voltage. Normal fluctuation shall
be within 10% of the rated voltage on the nameplate.
2. Supply voltage is too low and load is too high.
3. Measure the current of live wire on main board.
If the current isn’t higher than the overcurrent
protection value, please check the controller.
4. The indoor and outdoor heat exchangers are too
dirty, or the air inlet and air outlet are blocked.
5. The fan motor is not running. Abnormal fan speed:
fan speed is too low or the fan doesn’t run
6. The compressor is not running normally. There is
abnormal sound, oil leakage or the temperature of
the shell is too high, etc.
7. There’s blockage in the system (filth blockage, ice
plug, greasy blockage, Y-valve hasn’t been opened
completely)
6
Zero-crossing
inspection
circuit
malfunction
of the IDU fan
motor
U8
Blinks 17
times
every 3s
Operation of remote
controller or control panel is
available, but the unit won’t
act.
1. Quick de-energization and energization. Wrong
judgement by the controller because the electric-
discharging of capacitor is slow.
2. Zero-crossing inspection circuit of main board for
controller is abnormal.
