Mitsubishi Electric MSZ-FD25VA Service Manual page 24

10-3. INSTRUCTION OF TROUBLESHOOTING
Start
Indoor unit
operates.
Outdoor unit
doesn't
operate.
Outdoor unit Outdoor unit
operates only doesn't
in Test Run operate
operation. w
even in
Test Run
operation. w
Refer to
Check room
"How to check
temperature
inverter/
thermistor.
compressor".
Refer to 10-7.
"Test point
diagram and
voltage".
All lamps POWER lamp
Flash on and off
Flash on and off
at 0.5-second
at 0.5-second
intervals
intervals
Cause:
Cause:
Indoor unit
Indoor/
• The horizontal
Outdoor unit
vane is not
• Miswiring
installed
or trouble
correctly.
of serial signal
Refer to 10-6. Refer to 10-6.
E "Check of D "How to
installation of check of
the horizontal miswiring
vane". and serial
signal error.
Indoor unit operates.
Outdoor unit doesn't
operate normally.
Unit doesn't Indoor unit
operates, when
operate
EMERGENCY
normal
OPERATION
operation in
switch is pressed.
COOL or
HEAT mode.
Refer to Refer to 10-6.B
"Check of "Check of
R.V. coil". remote controller
and receiver
P.C. board".
POWER lamp POWER lamp
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
Check room Refer to 10-6.
A "Check of
temperature
thermistor indoor fan
and indoor motor".
coil thermis-
tor.
Refer to 10-7.
"Test point
diagram and
voltage".
w"Test Run operation"
means the operation
within 30 minutes after
EMERGENCY OPERATION
switch is pressed.
Indoor unit
doesn't receive
the signal from
remote controller.
Indoor unit
doesn't operate,
when
EMERGENCY
OPERATION
switch is pressed.
1. Check indoor / outdoor
connecting wire.
(Check if the power
is supplied to the
indoor unit.)
2. Refer to 10-6.C
"Check of indoor
electronic control
P.C. board and indoor
fan motor".
POWER lamp POWER lamp
4-time flash 5-time flash
Cause: Cause:
Indoor unit Outdoor unit
• Trouble of • Outdoor
indoor unit power
system
control
abnormality
system
Replace the Refer to
indoor "How to check
electronic inverter/
compressor".
control
P.C. board.
24
If blinking of OPERATION
INDICATOR lamp cannot
be checked, it can be checked
with failure mode recall function.
OPERATION
INDICATOR
lamp on the
indoor unit is
flashing on
and off.
PLASMA lamp 2-time flash
cause:
Indoor unit
• Trouble of PLASMA
operation
Refer to 10-6.F"Check of
PLASMA operation".
Refer to outdoor unit service manual.
POWER lamp POWER lamp
6-time flash 7-time flash
Cause: Cause:
Outdoor unit Outdoor unit
• Trouble of • Trouble of
thermistor outdoor
in outdoor control
unit system
Refer to Replace the
"Check of inverter P.C.
outdoor board or
thermistors". the outdoor
electronic
control P.C.
board.
POWER lamp
14-time flash
Cause:
Outdoor unit
• Other
abnormality
Check
"Flow chart of
the detailed
outdoor unit
failure mode
recall function."