Service manual

109
Indication
Abnormal point Detecting method
Symptom: Outdoor unit operates.
Check points
LED 1
(Red)
Lighting 6 times Power factor detection When the compressor power factor cannot be detected. • Check the compressor wiring.
• Check the characteristic of the defrost
temperature thermistor.
• Check the connector. (CN662)
Lighting 9 times Service mode
Lighting 5 times Defrost thermistor
When operating unit with compressor relay connector disconnected.
Lighting 8 times
Active filter module protection When active filter module self-protection has been performed.
When a short or open circuit occurs in the defrost thermistor during
heating.
LED 2
(Yellow)
Indication
Abnormal point Detecting method
Symptom: Outdoor unit operates (The compressor operates at reduced frequency)
Check points
LED 1
(Red)
These symptoms do not mean any
abnormality of the product, but check
the following points.
• Air filter clogging.
• Amount of gas.
• Short cycle of indoor/outdoor air flow.
Once Lighting Current protection
When the outdoor unit input current exceeds 13A.
6 times Lighting Overload protection When the compressor load exceeds the specified value.
Twice Lighting High pressure protection When indoor pipe temperature exceeds 55 ˚C during heating.
Twice Lighting Defrosting in cooling When indoor pipe temperature falls to 6 ˚C or below during cooling.
3 times Lighting
Discharge temperature
protection
When the discharge temperature exceeds 104 ˚C .
4 times Lighting
Low discharge
temperature protection
When the state with low discharge temperature of which 37 ˚C or below
in COOL and 35
˚C or below in HEAT for 20 minutes.
5 times Lighting High pressure protection When high pressure protect thermistor detects 58: or more.
LED 2
(Yellow)
Measure the resistance between the terminals with a tester.
(Coil wiring temperature10°C ~ 30°C)
Room
temperature
thermistor (RT11)
13-4. Trouble criterion of main parts
Part name
Indoor coil
thermistor (RT12)
Indoor fan
motor (MF)
INNER FUSE
136i3°C
CUT OFF
Motor partSensor part
Check method and criterion
Measure the resistance with a tester.
(Part temperature 10°C ~ 30°C)
Measure the voltage Power ON.
Figure
8kΩ ~ 20kΩ
Normal
Abnormal
Open or
short-circuit
396 ~ 430ΩWHT-BLK
BLK-RED
BRN-YLW
YLW-GRY
Normal
4.5 ~ 5.5V
Abnormal
Remain 0V or 5V
(When fan revolved one time)
0V➔5V➔0V
(Approx.)
MSC-A07/A09WV
320 ~ 348Ω
RED
BLK
YLW
FUSE
GRY
BRN
WHT
MSC-A07WV -
MSC-A09WV -
MSC-A12WV -
E1
E1
E1
Normal
Abnormal
Open or
short-circuit
MSC-A07/A09/A12WV
MSC-A07/A09/A12WV
Vane motor
(MV)
Measure the resistance between the terminals with a tester.
(Part temperature10°C ~ 30°C)
Normal
Abnormal
Open or
short-circuit
240 ~ 260Ω
RED
YLW
BRN
ORN
GRN
ROTOR
MSC-A07/A09/A12WV
Color of
lead wire
303 ~ 329Ω
MSC-A12WV
287 ~ 311Ω
Color of
lead wire
OB307A4.qxp 03.2.19 4:11 PM Page 109