33
Error Code Abnormal point and detection method
Case
Judgment and action
U9
(4220)
Detailed
codes
To find out the detail history (latest) about U9 error, turn ON SW2-1, 2-2, 2-6.
Refer to 10-10.
01
Overvoltage error
• Increase in DC bus voltage to
420V
1
Abnormal increase in power source
voltage
2
Disconnection of compressor wiring
3
Defective outdoor power circuit
board
4
Compressor has a ground fault.
1
Check the field facility for the power
supply.
2
Correct the wiring (U.V.W phase) to
compressor. Refer to 10-9 (Outdoor
power circuit board).
3
Replace outdoor power circuit board.
4
Check compressor for electrical insula-
tion. Replace compressor.
02
Undervoltage error
• Instantaneous decrease in DC
bus voltage to 200V
1
Decrease in power source voltage,
instantaneous stop.
2
Disconnection or loose connection
of CN52C on the outdoor noise f lter
circuit board/controller circuit board
3
Defective converter drive circuit of
outdoor power circuit board
4
Defective 52C drive circuit in outdoor
noise f lter circuit board
1
Check the f eld facility for the power
supply.
2
Check CN52C wiring.
3
Replace outdoor power circuit board.
4
Replace outdoor noise f lter circuit
board.
04
Input current sensor error/
L1-phase open error
• Decrease in input current
through outdoor unit to 0.1A
only if operation frequency is
more than or equal to 40Hz
or compressor current is more
than or equal to 6A.
1
Disconnection or loose connection
between TB1 and outdoor noise f lter
circuit board
2
Disconnection or loose connection
of CN5 on the outdoor power circuit
board/CNCT on the outdoor noise
f lter board
3
Defective ACCT(AC current trans) on
the outdoor noise f lter circuit board
4
Defective input current detection
circuit of outdoor power circuit board
5
Defective outdoor controller circuit
board
1
Check the wiring between TB1 and
outdoor noise f lter circuit board
2
Check CN5 wiring.
3
Replace outdoor noise f lter circuit
board.
4
Replace outdoor power circuit board.
5
Replace outdoor controller circuit board.
08
Abnormal power synchronous
signal
• No input of power synchronous
signal to power circuit board
• Power synchronous signal
of 44 Hz or less, or 65 Hz or
more is detected on power
circuit board.
1
Distortion of power source voltage,
Noise superimposition.
2
Disconnection or loose connection of
earth wiring
3
Disconnection or loose connection
of CN2 on the outdoor power circuit
board /controller circuit board
4
Defective power synchrous signal
circuit in outdoor controller circuit
board
5
Defective power synchrous signal
circuit in outdoor power circuit board
1
Check the f eld facility for the power
supply.
2
Check earth wiring.
3
Check CN2 wiring.
4
Replace outdoor controller circuit board.
5
Replace outdoor power circuit board.
10
PFC error (Overvoltage/
Undervoltage/Overcurrent)
• PFC detected any of the fol-
lowings
a) Increase in DC bus voltage
to 420V
b) Decrease in PFC control
voltage to 12V DC or lower
c) Increase in input current to
50A peak
1
Abnormal increase in power souce
voltage
2
Decrease in power source voltage,
instantaneous stop.
3
Disconnection of compressor wiring
4
Misconnection of reactor (ACL)
5
Defective outdoor power circuit
board
6
Defective Reactor(ACL)
7
Disconnection or loose connection
of CN2 on the outdoor power circuit
board/controller circuit board
12
Check the f eld facility for the power
supply.
3
Correct the wiring (U.V.W phase) to
compressor. Refer to 10-9 (Outdoor
power circuit board).
4
Correct the wiring of reactor (ACL)
5
Replace outdoor power circuit board.
6
Replace Reactor (ACL).
7
Check CN2 wiring.
20
PFC/IGBT error
(Undervoltage)
• When Compressor is running,
DC bus voltage stays at 310V
or lower for consecutive 10
seconds.
1
Incorrect switch settings on the
outdoor controller circuit board for
model select
2
Defective outdoor power circuit board
3
Defective outdoor controller circuit
board
1
Correction of a model select
2
Replace outdoor power circuit board.
3
Replace outdoor controller circuit board.
OCH544
