13
No.
1
w
2
4
5
6
Symptom
Operation indicator lamp
Detection method
Check point
Left lamp flashes.
0.5-second ON
0.5-second OFF
Mis-Wiring
Outdoor
power
system
Outdoor
thermistors
Outdoor
control
system
Indoor coil
thermistor
3 minutes after power supply turns ON, when
serial signal is not received.
When compressor has stopped due to over
current protection or start-up failure protection
3 times in a row within 5 seconds after start-
up.
<Thermistor short>
Thermistors are abnormal when they short
after compressor start-up.
<Thermistor open>
Thermistors are abnormal when they open
after compressor start-up.
However, discharge temperature thermistor is
abnormal when open circuit is detected more
than 10 minutes after compressor start-up.
When it cannot properly read data in the
nonvolatile memory of outdoor electronic
control P.C. board.
• Shortage of refrigerant
• Replace the outdoor control
P.C. board.
Refer to "Check of outdoor
thermistor".
Refer to service manual
OB328 or OB319.
• Refer to "Check of inverter/
compressor".
Refer to service manual
OB328 or OB319.
• Replace the outdoor
electronic control P.C. board or
inverter P.C. bpard.
Refer to service manual
OB328 or OB319.
• Refer to
D
"How to check
mis-wiring " on page 16.
w
3
Indoor fan
motor
7
Abnormal
point
Outdoor unit
does not
operate.
Room
tempera-
ture
thermistor
Left lamp flashes.
2-time flash
2.5-second OFF
Detect Indoor coil/room temperature
thermistor short or open circuit every 8
seconds during operation.
• Refer to the characteristics of
indoor coil thermistor,
sub indoor coil
thermistor, and room
temperature thermistor on
page 18.
Left lamp flashes.
3-time flash
2.5-second OFF
Indoor fan
repeats 12
seconds ON
and 3
minutes
OFF.
When the
indoor fan
breaks, the
fan keeps
stopping.
When rotational frequency feedback signal is
not emit during 12-second indoor fan
operation.
• Refer to
A
"Check of
indoor fan motor" on page 14.
Left lamp flashes.
4-time flash
2.5-second OFF
Indoor
control
system
When it cannot properly read data in the
nonvolatile memory of indoor electronic
control P.C. board.
Outdoor unit
does not
operate.
Outdoor unit
does not
operate.
• Replace the indoor electronic
control P.C. board.
Left lamp flashes.
5-time flash
2.5-second OFF
Left lamp flashes.
6-time flash
2.5-second OFF
Outdoor unit
does not
operate.
Outdoor unit
does not
operate.
Outdoor unit
does not
operate.
8
0.5-second ON
0.5-second OFF
When the electricity is not conducted to the
safety device (FAN) of the horizontal vane.
• Refer to
E
"Check of
installation of the horizontal
vanes" on page 17.
Indoor unit
and outdoor
unit do not
operate.
Attachment
of the
horizontal
vane
Both lamps flash at the same time.
Operation Indicator
Both lamp
MXZ type
Operation
mode
setting
Lighted
Flashing
Outdoor unit
operates but
indoor unit
does not
operate.
When the operation mode of each indoor unit
is differently set to COOL(includes DRY) and
HEAT at same time, the operation mode of
indoor unit that has operated at first has the
priority.
• Unify the operation mode.
Refer to service manual
OB319.
Left lamp flashes.
7-time flash
2.5-second OFF
2.5-second OFF
NOTE :
w
When the indoor unit has started operation and the above detection method has detected an abnormality (the first
detection after the power ON), the indoor electronic control P.C. board turns OFF the 52C and the indoor fan motor
with the OPERATION INDICATOR lamp lighting.
When the 52C and the indoor fan motor are turned ON again 3 minutes later and the same abnormality is detected
(a second detection of the above abnormality after the power ON), the indoor electronic control P.C. board turns
OFF the 52C and the indoor fan motor with the OPERATION INDICATOR lamp flashing.
However, the first detection is cleared in case the power is turned OFF after the first detection.
1. Troubleshooting check table
NOTE : Before taking measures, make sure that the symptom reappears for accurate troubleshooting.
Self check table
Operation Indicator
· Flashing of the OPERATION INDICATOR lamp (on the left or both)
indicates possible abnormalities.
· The OPERATION INDICATOR lamp (on the left) is
lighting during normal operation.
flashing
• The following indication applies regardless of shape of the indicator.
OB327 --1qxp 04.1.8 1:41 PM Page 13
