Mitsubishi Electric MSH-C18TV Service Manual page 36

11-2. Instruction of troubleshooting
Start
Indoor unit
operates.
Outdoor unit
doesn't
operate.
Outdoor unit
doesn't
Outdoor unit
operate
operates in
even in
only Test Run
Test Run
operation.
operation.
Check room
temperature
Refer to D
thermistor.
"Check of
Refer to
outdoor unit"
"Test point
on page 40
diagram and
or 41.
voltage" on
page 44.
1-time flash
Flash on and
Cause:
off at 0.5-
Indoor/
second interval
Outdoor unit
Cause:
• Trouble of
Indoor/
serial signal
Outdoor unit
• Mis-wiring
Refer to G "How to
check mis-wiring and
sirial singal error
(When outdoor unit
doesn't operate)"
on page 43.
1
Indoor unit
operates.
Outdoor unit
doesn't operate
normally.
MSH-C24TV only
Unit doesn't
Outdoor
operate
unit doesn't
normal
stop even
operation in
if indoor unit
COOL or
stops.
HEAT mode.
Refer to F
Refer to E
"Check of
"Check of
R.V. coil"
outdoor unit"
on page 42.
on page 41.
2-time flash
3-time flash
Cause:
Cause:
Indoor unit
Indoor unit
• Trouble of
• Trouble of
room temp-
indoor fan
erature/
motor
indoor coil
thermistor
Refer to A
Check room
"Check of
temperature
indoor fan
thermistor
motor"
and indoor
on page 39.
coil thermis-
tor.
Refer to
"Test point
diagram and
voltage"
on page 44.
1<The case of the trouble of the serial signal>
When the power is turned off and then turned on
again, the indication shows "the trouble of mis-
wiring."
Indoor unit
doesn't receive
the signal from
remote controller.
Indoor unit
operates, when
the EMERGENCY
OPERATION
switch is pressed.
Refer to B
"Check of
remote controller
and receiver
P.C. board"
on page 39.
MSH-C24TV only
6-time flash
7-time flash
Cause:
Cause:
Outdoor unit
Outdoor unit
• Trouble of
• Trouble of
thermistor
outdoor unit
in outdoor
control
unit
system
Replace the
Refer to H
deicer
"Check of
P.C. board.
outdoor
thermistor"
on page 43.
36
OPERATION INDICATOR
lamp on the indoor unit is
flashing on and off.
Indoor unit
doesn't operate,
when the
EMERGENCY
OPERATION
switch is pressed.
1. Check indoor /
outdoor
connecting wire.
2. Refer to C
"Check of indoor
electronic control
P.C. board"
on page 40.