24
10-4. TROUBLESHOOTING CHECK TABLE
OPERATION INDICATOR
Not lighted
Blinking
Lighted
Before taking measures, make sure that the symptom reappears for accurate troubleshooting.
When the indoor unit has started operation and detected an abnormality of the following condition (the first detection after the
power ON), the indoor fan motor turns OFF and OPERATION INDICATOR lamp flashes.
NOTE
: The indoor unit may have been connected to a non-low-standby-power model outdoor unit. To use a low-standby-power
model, clear the error history by referring to “Deleting the memorized abnormal condition” described in 10-2.1. When
the error history is being cleared, the connection information also will be initialized. The indoor unit will be compatible
with a low-standby-power model after initialization. If the operation indicator lamp continues to f ash as shown in No.1
after the procedure, refer to 10-6. “How to check miswiring and serial error”.
Left lamp flashes.
7-time flash
2.5-second OFF
Left lamp flashes.
14-time flash or more
2.5-second OFF
No.
1
2
5
6
Symptom
Operation indicator lamp
Condition
Remedy
Left lamp flashes.
0.5-second ON
0.5-second OFF
Miswiring
or serial
signal
Outdoor
power
system
Outdoor
thermistors
Outdoor
control
system
Indoor coil
thermistor
The serial signal from the outdoor unit is not
received for a maximum of 6 minutes.
The indoor unit is connected to a
low-standby-power model after once
connected to a non-low-standby-power model.
It consecutively occurs 3 times that the
compressor stops for overcurrent protection or
start-up failure protection within 1 minute after
start-up.
The outdoor thermistors short or open circuit
during the compressor operation.
It cannot properly read data in the nonvolatile
memory of the inverter P.C. board or the
outdoor electronic control P.C. board.
• Refer to "Check of outdoor
thermistor".
Refer to the outdoor unit
service manual.
• Refer to "Check of inverter/
compressor".
Refer to the outdoor unit
service manual.
Check the stop valve.
• Replace the inverter P.C.
board or the outdoor electronic
control P.C. board.
Refer to the outdoor unit
service manual.
3 Indoor fan
motor
7
Abnormal
point
Room
tempera-
ture
thermistor
Left lamp flashes.
2-time flash
2.5-second OFF
The indoor coil or the room temperature
thermistor is short or open circuit.
• Refer to the characteristics of
indoor coil thermistor, and the
room temperature thermistor
on 10-7.
Left lamp flashes.
3-time flash
2.5-second OFF
The rotational frequency feedback signal is
not emitted during the indoor fan operation.
• Refer to 10-6. "How to check
miswiring and serial signal
error".
• Refer to
NOTE
.
• Refer to 10-6. "Check of
indoor fan motor".
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
Left lamp flashes.
5-time flash
2.5-second OFF
Left lamp flashes.
6-time flash
2.5-second OFF
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
Other
abnormality
An abnormality other than above mentioned is
detected.
• Check the stop valve.
• Check the 4-way valve.
• Check the abnormality in
detail using the failure mode
recall function.
Refer to the outdoor unit
service manual.
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
8
4
Left lamp flashes.
4-time flash
2.5-second OFF
Indoor
control
system
It cannot properly read data in the nonvolatile
memory of the indoor electronic control P.C.
board.
Indoor unit
and outdoor
unit do not
operate.
• Replace the indoor electronic
control P.C. board.
Outdoor
control
system
It cannot properly read data in the nonvolatile
memory of the inverter P.C. board or the
outdoor electronic control P.C. board.
• Check the blinking pattern of
the LED on the inverter P.C.
board or the outdoor electronic
control P.C. board.
9
Outdoor unit
does not
operate.
Left lamp lights up
OBH666C
