Troubleshooting - Mitsubishi Electric MS09NW*2 Technical & Service Manual

9

TROUBLESHOOTING

MUM18NW
9-1 Cautions on troubleshooting
9-1-1 Before troubleshooting, check the followings:
1) Check the power supply voltage.
2) Check the indoor/outdoor connecting wire for mis-wiring.
9-1-2 Take care the followings during servicing.
1) Befor servicing the air conditioner, be sure to first turn off the remote controller to stop the main unit, and then after
confirming the horizontal vane is closed, disconnect the breaker.
2) When removing the P.C. board, hold the edge of the board with care NOT to apply stress on the components.
3) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
9-2 Trouble criterion of main parts
Part name
Measure the resistance between the terminals with a tester.
(Coil wiring temperature-10¡C ~ 40¡C)
Compressor
Measure the resistance between the terminals with a tester.
(Coil wiring temperature-10¡C ~ 40¡C)
Outdoor fan
motor
12
Check method and criterion
Normal
C-R 0.86~1.06'
C-S 1.94~2.39'
Normal
WHT-BLK 17.6~21.6'
BLK-YLW 9.1~11.3'
YLW-RED 9.1~11.3'
Abnormal
Opened or
short-circuited
Abnormal
Opened or
short-circuited
Figure
P
BLK YLW RED ORN WHT