26
No. Abnormal
point
Operation indicator lamp
Symptom
Condition
Remedy
1
Miswiring
or serial
signal
Left lamp blinks.
0.5-second ON
0.5-second OFF
Indoor unit and
outdoor unit do
not operate.
The serial signal from the outdoor unit is not
received for a maximum of 6 minutes.
• Refer to 9-6. "How to check
miswiring and serial signal er-
ror".
2
Outdoor
control
system
Left lamp lights up
It cannot properly read data in the nonvolatile
memory of the deicer P.C. board.
• Check the blinking pattern of
the LED on the deicer P.C.
board.
3
Indoor coil
thermistor
Left lamp blinks.
2-time blink
2.5-second OFF
The indoor coil or the room temperature ther-
mistor is short or open circuit.
• Refer to the characteristics of
indoor coil thermistor, and the
room temperature thermistor
(9-7.).
Room tem-
perature
thermistor
4
Indoor fan
motor
Left lamp blinks.
3-time blink
2.5-second OFF
The rotational frequency feedback signal is
not emitted during the indoor fan operation.
• Refer to 9-6. "Check of in-
door fan motor".
5
Indoor con-
trol system
Left lamp blinks.
4-time blink
2.5-second OFF
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.
6 Outdoor
thermistors
Left lamp blinks.
6-time blink
2.5-second OFF
The outdoor thermistors short or open circuit
during the compressor operation.
• Refer to "Check of outdoor
thermistor".
Refer to outdoor unit service
manual.
7
Outdoor
control
system
Left lamp blinks.
7-time blink
2.5-second OFF
It cannot properly read data in the nonvolatile
memory of the deicer P.C. board.
• Replace the deicer P.C. board.
Refer to outdoor unit service
manual.
8
*1
Refrigerant
circuit
*2 on 9-3
Left lamp blinks.
14-time blink or more
2.5-second OFF
The unit has been pumped down for a long
time.
• Check the stop valve.
The refrigerant amount is low.
• Check the connections and the
refrigerant amount for any leak-
age.
The unit is short cycling.
• Check for short cycle.
If any problem is found, provide
some space for air path around
the outdoor unit.
The outdoor fan motor locks up.
• Check that the connecting ca-
ble of the outdoor fan motor is
properly connected.
• Check the resistance value
of the outdoor fan motor.
If any problem is found, replace
the outdoor fan motor.
An abnormality of the indoor thermistors or
ambient temperature thermistor is detected.
• Refer to “TEST POINT DIA-
GRAM AND VOLTAGE” on the
service manual of indoor and
outdoor unit for the characteris-
tics of the thermistors. (Do not
start the operation again with-
out repair to prevent hazards.)
*1. When the trouble indicated with 14-time blink or more occurs, turn off the main power supply.
Otherwise, the operation indicator lamp may blink again even if the power is turned off and on using a remote controller.
OPERATION INDICATOR
Lit
Not lit
MS-CP30VA
OBH782A
