Filter
Top Products
42
Check
code
Diagnosis of malfunction Cause Check points
4
Abnormality of drain sensor 1) Bad contact of transmission
wire
2) Damaged thermistor
1) Check the connector.
2) Measure the resistance of the thermistor
(between ➃ - ➄of CN50).
As for the normal resistance, refer to the case
of 1.
If the resistance is normal, replace the indoor con-
troller board.
5
Malfunction of drain pump 1) Malfunction of drain pump
2) Damaged drain sensor
1) Check the drain pump.
2) ● Check the drain sensor.
● Check the drain sensor heater. Normal resis-
tance should be 82Ω. (between 1 - 3of
CN50).
If the resistance is normal, replace the indoor con-
troller board.
6
Coil frost protection is work-
ing.
1) Short cycle of air cycle
2) Dirty air filter
3) Damaged fan
4) Abnormal refrigerant
1) Clear obstructions from the air cycle.
2) Clean the air filter
3) Check the fan.
4) Check the refrigerant temperature.
8
Abnormality in outdoor unit
❈ The number of check code shows times of Buzzer sound.
1) Wrong wiring of indoor/outdoor
connecting wire
2) Reversed phase
3) Protection device is working
4) Damaged outdoor coil thermis-
tor
1) Check the indoor/outdoor connecting wire.
2) Change the connection of electric wiring.
3) Check the protection device.
4) Measure the resistance of the outdoor coil ther-
mistor. If the resistance is normal, replace the
outdoor controller board.
1
2
Abnormality of room temper-
ature thermistor (RT1)
Abnormality of indoor coil
thermistor (RT2)
1) Bad contact of thermistor
2) Damaged thermistor
1) Check the thermistor.
2) Measure the resistance of the thermistor.
Normal resistance should be as follows.
32°F····15kΩ 86°F·····4.3kΩ
50°F······9.6kΩ 104°F·····3.0kΩ
68°F······6.3kΩ
If the resistance is normal, replace the indoor
controller board.
Unit stops after 5 to
20 seconds operation
Protection function is working.
Refer to check code on remote controller display.
Auto vanes do not work.
Auto vane motor does not work.
Connector is poorly connected.
Auto vane motor is poorly assembled.
Indoor controller board is damaged.
Auto vane motor is damaged.
Auto vane motor relay is damaged.
Power ON/OFF button
is not available.
Indoor/outdoor connecting wire is connected
incorrectly.
Indoor/outdoor connecting wire shorts.
Compressor protector is damaged.
Defroster is broken.
Remote controller is damaged.
Transmission wire is poorly connected
Transmission wire is damaged.
Connector is poorly connected.
2. OTHER TROUBLES AND CAUSES
OC276-A-2.qxp 03.11.25 9:06 AM Page 42