31
Error Code
Abnormal point and detection method
Case
Judgment and action
U9
(4220)
Overvoltage or voltage shortage and
synchronous signal to main circuit
Abnormal if any of followings are detected
during compressor operation;
• Decrease of DC bus voltage to 310V
•
Instantaneous decrease of DC bus voltage
to 200V
•
Increase of DC bus voltage to 400V
• Decrease of input current of outdoor unit
to 0.5A only if operation frequency is more
than or equal to 40Hz or compressor
current is more than or equal to 5A.
• Abnormal power synchronous (zero cross)
signal
1
Decrease of power supply
voltage
2
Disconnection of compressor
wiring
3
Disconnection or loose
connection of CN52C
4
Defective ACT module
5
Defective ACT module drive
circuit of outdoor power circuit
board
6
Disconnection or loose
connection of CNAF
7
Defective 52C drive circuit of
outdoor noise filter circuit board
8
Disconnection or loose
connection of CN5 on the
outdoor power circuit board
9
Disconnection or loose
connection of CN2 on the
outdoor power circuit board
1
Check the facility of power supply.
2
Correct the wiring (U·V·W phase) to
compressor. Refer to 10-9 (Outdoor power
circuit board).
3
Check CN52C wiring.
4
Replace ACT module.
5
Replace outdoor power circuit board.
6
Check CNAF wiring.
7
Replace outdoor noise filter circuit board.
8
Check CN5 wiring on the outdoor power
circuit board. Refer to 10-9.
9
Check CN2 wiring on the outdoor power
circuit
board.
Refer to 10-9.
UF
(4100)
Compressor overcurrent interruption
(When compressor locked)
Abnormal if overcurrent of DC bus or
compressor is detected within 30 seconds
after compressor starts operating.
1
Stop valve is closed.
2
Decrease of power supply
voltage
3
Looseness, disconnection or
converse of compressor wiring
connection
4
Defective compressor
5
Defective outdoor power board
6
Dip Switch setting for selecting
model is incorrect on the
outdoor power circuit board.
1
Open stop valve.
2
Check facility of power supply.
3
Correct the wiring (U·V·W phase) to
compressor.
Refer to 10-9 (Outdoor power circuit board).
4
Check compressor.
Refer to 10-6.
5
Replace outdoor power circuit board.
6
Check that the Dip Switch setting is correct
on the outdoor power circuit board by
referring to "Model Select" in "1) Function of
switches" in 10-10.
UH
(5300)
Current sensor error
•
Abnormal if current sensor detects –1.5A
to 1.5A during compressor operation.
(This error is ignored in case of test run
mode.)
w
This error is ignored in case of test run
mode.
•
It’s abnormal for 38A the input current or
10 seconds continuous 34A or more.
1
Disconnection of compressor
wiring
2
Defective circuit of current
sensor on outdoor power circuit
board
3
Decrease of power supply
voltage
1
Correct the wiring (U·V·W phase) to
compressor. Refer to 10-9 (Outdoor power
circuit board).
2
Replace outdoor power circuit board.
3
Check the facility of power supply.
U8
(4400)
Outdoor fan motor
Abnormal if the rotational frequency of fan
motor is not detected during DC fan motor
operation.
Fan motor rotational frequency is abnormal
if;
• 100 rpm or below detected continuously
for 15 seconds at 20
:
[68˚F] or more
outside air temperature.
• 50 rpm or below or 1500 rpm or more
detected continuously for 1 minute.
1
Failure in the operation of the
DC fan motor
2
Failure in the outdoor circuit
controller board
1
Check or replace the DC fan motor.
2
Check the voltage of the outdoor circuit
controller board during operation.
3
Replace the outdoor circuit controller board.
(when the failure is still indicated even after
performing the action
1
above.)
OCH512