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12
As for outdoor unit MUZ type, refer to service manual OB346.
As for outdoor unit MXZ type, refer to service manual OB319.
Start
Indoor unit
operates.
Outdoor unit
does not
operate.
Indoor unit
does not receive
the signal from
remote controller.
OPERATION INDICATOR
lamp on the indoor unit is
flashing on and off.
Outdoor unit
operates in
only Test Run
operation.
Outdoor unit
does not
operate
even in
Test Run
operation.
Indoor unit
operates, when
the EMERGENCY
OPERATION
switch is pressed.
Indoor unit
does not operate,
when the
EMERGENCY
OPERATION
switch is pressed.
Check room
temperature
thermistor.
Refer to
"Test point
diagram and
voltage" on
page 18 and 19.
Refer to
"Check of
inverter/
compressor".
Refer to
"Check of
remote controller
and receiver
P.C. board".
1. Check indoor/ outdoor
connecting wire.
(Check if the power
is supplied to the
indoor unit.)
2. Refer to
"Check of indoor
electronic control
P.C. board".
Unit does not
operate
normal
operation in
COOL or
HEAT mode.
Refer to
"Check of
R.V. coil".
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 temp-
erature/
indoor coil
thermistor
3-time flash
Cause:
Indoor unit
• Trouble of
indoor fan
motor
5-time flash
Cause:
Outdoor unit
• Outdoor
power
system
abnormality
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit
7-time flash
Cause:
Outdoor unit
• Trouble of
outdoor
control
system
Refer to
D
"How to
check mis-
wiring and
serial signal
error (When
outdoor unit
does not
work)" on
page 17.
Check room
temperature
thermistor
and indoor
coil thermis-
tor.
Refer to
"Test point
diagram and
voltage" on
page 18 and
19.
Refer to
A
"Check of
indoor fan
motor" on
page 15.
Refer to
"Check of
inverter/
compressor".
Refer to
"Check of
outdoor
thermistors".
Replace the
outdoor
electronic
control P.C.
board.
4-time flash
Cause:
Indoor unit
• Trouble of
indoor unit
control
system
Replace the
indoor
electronic
control
P.C. board.
Indoor unit operates.
Outdoor unit does not
operate normally.
8-2. Instruction of troubleshooting
OB345A