MITSUBISHI ELECTRIC Mitsubishi Split-Type - Manual (Page 14)

14
Start
Indoor unit
operates.
Outdoor unit
doesn't
operate. Indoor unit
doesn't 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.
w 1
Outdoor unit
doesn't
operate
even in
Test Run
operation.
w 1
Indoor unit
operates, when
EMERGENCY
OPERATION
switch is pressed. Indoor unit
doesn't operate,
when
EMERGENCY
OPERATION
switch is pressed.
Check room
temperature
thermistor.
Refer to 9-7.
"Test point
diagram and
voltage". Refer to
"How to check
inverter/
compressor". Refer to 9-6. B
"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 9-6.
C
"Check of indoor
electronic control
P.C. board and indoor
fan motor".
Unit doesn't
operate
normal
operation in
COOL or
HEAT mode.
Refer to
"Check of
R.V. coil".
Left lamp
Flash on and off
at 0.5-second
intervals
Cause:
Indoor/
Outdoor unit
• Mis-wiring
or trouble
of serial signal Left lamp
2-time flash
Cause:
Indoor unit
• Trouble of
room temp-
erature/
indoor coil
thermistor Left lamp
3-time flash
Cause:
Indoor unit
• Trouble of
indoor fan
motor Left lamp
5-time flash
Cause:
Outdoor unit
• Outdoor
power
system
abnormality Left lamp
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit Left lamp
7-time flash
Cause:
Outdoor unit
• Trouble of
outdoor
control
system
Refer to 9-6.
D "How to
check of
mis-wiring
and serial
signal error
(when
outdoor unit
doesn't work)".
All lamps
Flash on and off
at 0.5-second
intervals
Cause:
Indoor unit
• The horizontal
vane is not
installed
correctly.
Refer to 9-6.
E "Check of
installation of
the horizontal
vane".
Check room
temperature
thermistor
and indoor
coil thermis-
tor.
Refer to 9-7.
"Test point
diagram and
voltage". Refer to 9-6.
A "Check of
indoor fan
motor".
Refer to
"How to check
inverter/
compressor". Refer to
"Check of
outdoor
thermistors". Replace the
inverter P.C.
board or
the outdoor
electronic
control P.C.
board.
Left lamp
14-time flash
Cause:
Outdoor unit
• Other
abnormality
Check
"Flow chart of
the detailed
outdoor unit
failure mode
recall function."
Left lamp
4-time flash
Cause:
Indoor unit
• Trouble of
indoor unit
control
system
Replace the
indoor
electronic
control
P.C. board.
As for outdoor unit MUZ type,
refer to service manual OB379.
As for outdoor unit MXZ type,
refer to service manual OB377.
Indoor unit operates.
Outdoor unit doesn't
operate normally.
If blinking of OPERATION
INDICATOR lamp cannot be
checked, it can be checked with
failure mode recall function.
w 1
"Test Run operation" means the
operation within 30 minutes after
EMERGNCY OPERATION switch
is pressed.
9-3. Instruction of troubleshooting
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