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2. Indoor unit failure mode table
The left lamp of
the OPERATION
INDICATOR lamp
Abnormal point
(Failure mode)
Condition
Remedy
Not lighted
Normal
—
—
1-time blink every
0.5-second
Room temperature
thermistor
The room temperature thermistor short or
open circuit is detected every 8 seconds dur-
ing operation.
Refer to the characteristics of the room temperature
thermistor (9-7.).
2-time blink
2.5-second OFF
Indoor coil
thermistor
The indoor coil thermistor short or open circuit
is detected every 8 seconds during operation.
Refer to the characteristics of the main indoor coil ther-
mistor, the sub indoor coil thermistor (9-7.).
3-time blink
2.5-second OFF
Serial signal
The serial signal from outdoor unit is not re
-
ceived for a maximum of 6 minutes.
Refer to 9-6. "How to check miswiring and serial
signal error".
11-time blink
2.5-second OFF
Indoor fan motor
The rotational frequency feedback signal is
not emitted for 12 seconds after the indoor fan
motor is operated.
Refer to 9-6. "Check of indoor fan motor".
12-time blink
2.5-second OFF
Indoor control
system
It cannot properly read data in the nonvolatile
memory of the indoor electronic control P.C.
board.
Replace the indoor electronic control P.C. board.
NOTE
: Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (9-4.).
3. Operation check on i-see sensor
While recalling the failure details, set the temperature to 66°F (19°C) to perform the simple check on the i-see sensor.
Place your hand over the i-see sensor, and the buzzer will beep at 1 second intervals. (Normal detection temperature range
is 93 to 102°F (34 to 39°C).)
If the buzzer does not beep, check for disconnection of the connectors.
Set the temperature to 73°F (23°C) to exit the simple check mode on the i-see sensor.
The left lamp of
the OPERATION
INDICATOR lamp
Abnormal point
(Failure mode)
Condition
Remedy
6-time blink
i-see sensor
Poor contact in i-see sensor wiring
Failure in loading corrected data of i-see
sensor
Check for disconnection of the connectors.
OBHT872
