Instruction Of Troubleshooting - Mitsubishi Electric MSH-07NV Service Manual

10-2 Instruction of troubleshooting

Indoor unit oper-
ates. Outdoor unit
doesn't operate.
Outdoor unit Outdoor unit
operates in doesn't oper-
only Test ate even in
Run opera- Test Run
tion. operation.
Refer to
Check room
"Check of
temperature
outdoor unit"
thermistor.
on page 52.
Refer to E
"How to check
mis-wiring and sig-
nal error
(when outdoor unit
doesn't work)"
on page 53 and
54. 1
48
Indoor unit
dosen't receive
the signal from
remote
controller.
Refer to
B
"Check of
receiver P.C.
board" on page
51.
1-time flash
D
Cause:indoor/outdoor unit
connecting
( Trouble of mis-wiring
Trouble of the serial signal
Start
OPERATION INDICATOR
lamp on the indoor unit is
flashing on and off.
2-time flash
2.5-second OFF
3-time flash
2.5-second OFF
Cause:Indoor unit
2-time-Room tempera-
ture/Indoor coil
thermistor trouble
3-time-Indoor fan motor
trouble
Refer to
Check indoor coil
"Check of indoor
thermistor. Refer
fan motor" on
to"Test point dia-
page 51.
gram and voltage"
on page 55,57 and
58.
1<The case of the trouble of the serial signal>
When turn off the power and then turn on the power again, the
indication shows "the trouble of mis-wiring."
Indoor unit doesn't
receive the signal from
remote controller.
Also, OPERATION INDI-
CATOR lamp doesn't
flash, when the EMER-
GENCY OPERATION
switch is pressed.
Refer to "Check of
C
indoor electronic control
P.C. board" on page 52.
6-time flash
2.5-second OFF
Cause:outdoor unit
6-time-Replace the out-
door thermistor
Check room temperature
A
thermistor. Refer to"Test
point diagram and volt-
age" on page 55,57 and
58.