Service manual

Error Code
Abnormal point and detection method
Case
Judgment and action
19
U9
Detailed
codes
To find out the details about U9 error, turn ON SW2-1, 2-2, 2-3, 2-4, 2-5 and 2-6 when U9 error occurs.
To find out the detail history (latest) about U9 error, turn ON SW2-1, 2-2 and 2-6.
Refer to 10-10.
01
Overvoltage error
• Increase in DC bus voltage to
420V
1
Abnormal increase in power source volt-
age
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
insulation. 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 filter
circuit board/controller circuit board
3 Defective converter drive circuit in
outdoor power circuit board
4 Defective 52C drive circuit in outdoor
noise filter circuit board
1 Check the field facility for the power
supply.
2 Check CN52C wiring.
3 Replace outdoor power circuit board.
4 Replace outdoor noise filter circuit
board.
04
Input current sensor 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 of
CN5 on the outdoor power circuit board/
CNCT on the outdoor noise filter board
2 Defective ACCT (AC current trans)
on the outdoor noise filter circuit
board
3 Defective input current detection
circuit in outdoor power circuit board
4
Defective outdoor controller circuit board
1 Check CN5/CNCT wiring.
2 Replace outdoor noise filter circuit
board.
3 Replace outdoor power circuit board.
4 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 synchronous signal
circuit in outdoor controller circuit
board
5 Defective power synchronous signal
circuit in outdoor power circuit board
1 Check the field 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 of 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 source
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
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.
12 Check the field 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
OCH525