Mitsubishi Electric MSZ-D30NA Service Manual page 22

9-3. INSTRUCTION OF TROUBLESHOOTING
Start
Indoor unit oper-
ates.
Outdoor unit
doesn't operate.
Outdoor unit Outdoor
operates only unit doesn't
in Test Run operate even
operation. in Test Run
operation.
Check room
Refer to "How
temperature
to check
thermistor.
inverter/
Refer to 8-7.
compressor".
"Test point
diagram and
voltage".
Left lamp Left lamp
Flash on and 2-time fl ash
off at 0.5-sec- Cause:
ond intervals Indoor unit
Cause: • Trouble of
Indoor/ Out- room tem-
door unit perature /
• Miswiring or indoor coil
trouble of thermistor
serial signal
Refer to 9-6. Check room
"How to temperature
check miswir- thermistor
ing and serial and indoor
signal error". coil thermis-
tor.Refer to
9-7."Test
point diagram
and voltage".
Indoor unit operates.
Outdoor unit doesn't
operate normally.
Indoor unit
Unit doesn't
operates, when
operate normal
EMERGENCY
operation in
OPERATION
COOL or HEAT
switch is pressed.
mode.
Refer to Refer to 9-6.
"Check of R.V. "Check of remote
coil". controller and
receiver P.C.
board".
Left lamp Left lamp
3-time fl ash 4-time fl ash
Cause: Cause:
Indoor unit Indoor unit
• Trouble of • Trouble
indoor fan of indoor
motor unit control
system
Refer to 9-6. Replace the
"Check of indoor elec-
indoor fan tronic control
motor". P.C. board.
Indoor unit
OPERATION INDICATOR
doesn't receive
lamp on the indoor unit is
the signal from
fl ashing on and off.
remote controller.
Indoor unit
doesn't operate,
when EMERGEN-
CY OPERATION
switch is pressed.
1.Check indoor / out-
door connecting wire.
(Check if the power is
supplied to the indoor
unit.)
2.Refer to 9-6. "Check
of indoor electronic
control P.C. board and
indoor fan motor".
Left lamp Left lamp
6-time fl ash
5-time fl ash
Cause: Cause:
Outdoor unit Outdoor unit
• Trouble of
• Outdoor
power thermistor in
outdoor unit
system
abnormality
Refer to "How Refer to
to check "Check of
inverter/ com- outdoor
pressor". thermistors".
22 22
If blinking of OPERATION INDI-
CATOR lamp cannot be checked,
it can be checked with failure
mode recall function.
"Test Run operation" means the
operation within 30 minutes after
EMERGENCY OPERATION
switch is pressed.
Refer to outdoor unit service manual.
Left lamp Left lamp
7-time fl ash 14-time fl ash
Cause: Cause:
Outdoor unit Outdoor unit
• Trouble of • Other ab-
outdoor con- normality
trol system
Replace the Check "Flow
inverter P.C. chart of the
board or the detailed
outdoor elec- outdoor unit
tronic control failure mode
P.C. board. recall func-
tion."