12
9-2. Instruction of troubleshooting
Start
Indoor unit
operates.
Outdoor unit
doesn't
operate.
Indoor unit
doesn't receive
the signal from
remote controller.
Indoor unit
operates.
Outdoor unit
doesn't operate
normally.
OPERATION INDICATOR
lamp on the indoor unit is
flashing on and off.
Outdoor unit
operates in
only Test Run
operation.
Outdoor unit
doesn't
operate
even in
Test Run
operation.
Indoor unit
operates, when
the EMERGENCY
OPERATION
switch is pressed.
Indoor unit
doesn't operate,
when the
EMERGENCY
OPERATION
switch is pressed.
Check room
temperature
thermistor.
Refer to 9-6.
"Test point
diagram and
voltage".
Refer to
"Check of
outdoor unit".
Refer to
"Check of
outdoor unit".
Refer to 9-5.
B
"Check of
remote controller
and receiver
P.C. board".
Flash on and
off at 0.5-
second
interval
Cause:
Indoor/
Outdoor unit
• Mis-wiring
or trouble of
serial signal
2-time flash
Cause:
Indoor unit
• Trouble of
room
temperature/
indoor coil
thermistor
Check room
temperature
thermistor
and indoor
coil
thermistor.
Refer to 9-6.
"Test point
diagram and
voltage".
4-time flash
Cause:
Indoor unit
• Trouble of
indoor
electric
P.C. board
Refer to 9-5.
D
"Check
of indoor
electric
control P.C.
board".
Refer to 9-5.
E
"How to
check mis-
wiring and
serial signal
error (When
outdoor unit
doesn't
work)".
1. Check indoor /
outdoor
connecting wire.
2. Refer to 9-5.
C
"Check of indoor
electronic control
P.C. board".
Outdoor unit
doesn't
stop even
if indoor unit
stops.
Unit doesn't
operate
normal
operation in
COOL or
HEAT mode.
Refer to
"Check of
R.V. coil".
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit
MXZ type
MUCFH-GA60VB
7-time flash
Cause:
Outdoor unit
• Trouble of
outdoor
control
system
Refer to
"Check of
outdoor
thermistor".
MUCFH-GA60VB
Replace the
deicer
P.C. board.
MXZ type
Replace the
outdoor
electronic
control
P.C. board.
MXZ type
5-time flash
Cause:
Outdoor unit
• Outdoor
power
system
abnormality
Refer to
"Check of
inverter/
compressor"
and "Check
of power
supply".
As for outdoor unit MUCFH type, refer to the service manual OB381.
As for outdoor unit MXZ type, refer to the service manual OB319 REVISED EDITION-A.
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