Service manual

16
MICROPROCESSOR CONTROL
6
6-1. 11-1. COOL ( ) OPERATION
1. Indoor fan speed control
Indoor fan operates continuously at the set speed by FAN SPEED CONTROL button regard-
less of thermostat’s OFF-ON.
In Auto the fan speed is as follows.
MSC-07RV - MU-07RV - MUH-07RV -
MSC-09RV - MU-09RV - MUH-09RV -
MSC-12RV - MU-12RV - MUH-12RV -
E4E4E4
E4E4E4
E4E4E4
1 deg.
1.7 deg.
3 deg.
Initial temperature difference
Room temperature minus set temperature : 1.7 degrees or more·····························High
Room temperature minus set temperature : Between 1 and 1.7 degrees·················Med.
Room temperature minus set temperature : less than 1 degree································Low
Fan speed
Difference between room
temperature and set tem-
perature during operation
1 deg.
1.7 deg.
4 deg.
Initial temperature difference
Room temperature minus set temperature : 2 degrees or more································High
Room temperature minus set temperature : Between 1 and 2 degrees····················Med.
Room temperature minus set temperature : less than 1 degree································Low
Fan speed
Difference between room
temperature and set tem-
perature during operation
MSC-07RV - MSC-07RV - MSC-07RV -
MSC-09RV - MSC-09RV - MSC-09RV -
MSC-12RV - MSC-12RV - MSC-12RV -
E3E2E1
E3E2E1
E3E2E1
MSC-07RV -
MSC-09RV -
MSC-12RV -
E4
E4
E4
2 deg.
TROUBLESHOOTING
7
Measure the resistance between the terminals with a tester.
(Coil wiring temperature10°C ~ 30°C)
7-1. Trouble criterion of main parts
Part name
Indoor fan
motor(MF)
INNER FUSE
136I3 CUT OFF
Motor part
Check method and criterion Figure
Normal
Abnormal
Open or
short-circuit
396 ~ 430Ω
WHT-BLK
BLK-RED
320 ~ 348Ω
RED
BLK
YLW
GRY
BRN
WHT
FUSE
Outdoor fan
motor(MF)
INNER FUSE
163I3 CUT OFF
Measure the resistance between the terminals with a tester.
(Coil wiring temperature –10°C ~ 40°C)
Normal
MU-07/09RV-
E4
311 ~ 381 Ω
283 ~ 347 Ω
265 ~ 325 Ω
292 ~ 359 Ω
WHT-BLK
BLK-RED
WHTRED
BLK
MAIN
AUX.
FUSE
Abnormal
Open or short-circuit
MU-12RV-
E4
Normal
MUH-07/09RV-
E4
311 ~ 381 Ω
283 ~ 347 Ω
265 ~ 325 Ω
292 ~ 359 Ω
WHT-BLK
BLK-RED
Abnormal
Open or short-circuit
MUH-12RV-
E4
MSC-07/09RV-
E4
MSC-12RV-
E4
396 ~ 430Ω
320 ~ 348Ω
MUH-07RV -
MUH-09RV -
MUH-12RV -
E4
E4
E4
MU-07RV -
MU-09RV -
MU-12RV -
E4
E4
E4
MSC-07RV -
MSC-09RV -
MSC-12RV -
E4
E4
E4
Color of
lead wire
Color of
lead wire
Color of
lead wire
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