Error Code
Abnormal point and detection method
Case
Judgment and action
26
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 10-8.
01
Overvoltage error
• Increase in DC bus voltage to
SW75VHA: 420V
SW100, 120VHA: 400V
SW100, 120YHA: 760V
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 10-7 (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
SW75, 100, 120VHA: 200V
SW100, 120YHA: 350V
1
Decrease in power source voltage,
instantaneous stop.
2
Disconnection or loose connection of
CN52C on the outdoor power circuit
board/controller circuit board (SW100,
120VHA)
3
Disconnection or loose connection
of CN52C on the outdoor noise filter
circuit board/controller circuit board
(SW75VHA)
4
Defective converter drive circuit in
outdoor power circuit board (SW·VHA)
5
Defective 52C drive circuit in outdoor
power circuit board (SW100, 120V/YHA)
6
Defective 52C drive circuit in outdoor
noise filter circuit board (SW75)
7
Defective outdoor converter circuit
board (SW·YHA)
8
Disconnection or loose connection
of rush current protect resistor RS
(SW·YHA)
9
Defective rush current protect
resistor RS (SW·YHA)
0
Disconnection or loose connection
of main smoothing capacitor CB
(SW100,120VHA)
1
Disconnection or loose connection
of CN2 on the outdoor power circuit
board /controller circuit board
(SW100,120VHA)
2
Power circuit failure on DC supply for
18V DC output on outdoor controller
circuit board (SW100,120VHA).
1
Check the field facility for the power
supply.
23
Check CN52C wiring. (SW·VHA)
4
Replace outdoor power circuit board.
(SW·VHA)
5
Replace outdoor power circuit board.
(SW100,120V/YHA)
6
Replace outdoor noise filter circuit
board. (SW75VHA)
7
Replace outdoor converter circuit
board. (SW·YHA)
8
Check RS wiring. (SW·YHA)
9
Replace RS. (SW·YHA)
0
Check CB wiring. (SW100,120VHA)
1
Check CN2 wiring. (SW100,120VHA)
2
Replace outdoor controller circuit
board. (SW100,120VHA)
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
L1-phase open (SW·YHA)
2
Disconnection or loose connection
between TB1 and outdoor noise filter
circuit board (SW75VHA/SW100,
120YHA)
3
Disconnection or loose connection of
CN5 on the outdoor power circuit board/
CNCT on the outdoor noise filter board
(SW75VHA/SW100, 120YHA)
4
Defective ACCT (AC current trans)
on the outdoor noise filter circuit
board (SW75VHA/SW100, 120YHA)
5
Defective input current detection
circuit in outdoor power circuit board
6
Defective outdoor controller circuit board
1
Check the field facility for the power
supply. (SW·YHA)
2
Check the wiring between TB1 and
outdoor noise filter circuit board.
(SW75VHA/SW100, 120YHA)
3
Check CN5/CNCT wiring. (SW75VHA/
SW100, 120YHA)
4
Replace outdoor noise filter circuit
board. (SW·YHA)
5
Replace outdoor power circuit board.
6
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.
OCH533A