Mitsubishi Electric MSZ-LN18VGW - E1 Service Manual page 26

10-3. INSTRUCTION OF TROUBLESHOOTING
1. Check of the unit.
*1. "Test Run operation" means the operation
Start
Indoor unit oper-
ates.
Outdoor unit
does not operate.
Outdoor unit Outdoor unit
operates only does not
in Test Run operate even
operation. *1. in Test Run
operation.*1.
Check room
Refer to "How
temperature to check
thermistor.
inverter/com-
Refer to 10-
pressor".
7. "Test point
diagram and
voltage".
POWER lamp
Flash on and
off at 0.5-sec-
ond intervals
Cause:
Indoor/Outdoor
unit
• Miswiring or
trouble of se-
rial signal
Refer to 10-
6. "How to
check mis-
wiring and
serial signal
error".
OBH766B
within 30 minutes after EMERGENCY
OPERATION switch is pressed.
Indoor unit operates.
Outdoor unit does
not operate normal-
ly.
Indoor unit
Unit does not
operates when
operate nor-
EMERGENCY
mal operation
OPERATION
in COOL or
switch is pressed.
HEAT mode.
Refer to Refer to 10-6.
"Check of R.V. "Check of remote
coil". controller and
indoor electronic
control P.C.
board".
POWER lamp POWER lamp
2-time fl ash 3-time fl ash
Cause: Cause:
Indoor unit Indoor unit
• Trouble • Trouble of
of room indoor fan
temperature motor
/ indoor coil
thermistor
Check room Refer to 10-
temperature 6. "Check
thermistor of indoor fan
and indoor motor".
coil thermis-
tor. Refer to
10-7."Test
point diagram
and voltage".
If blinking of OPERATION
INDICATOR lamp cannot be
checked, it can be checked with
failure mode recall function.
Indoor unit does
POWER lamp on the
not receive the
indoor unit is fl ashing
signal from re-
ON and OFF.
mote controller.
Indoor unit does
not operate when
EMERGENCY
OPERATION
switch is pressed.
1. Check indoor/out-
door connecting wire.
(Check if the power is
supplied to the indoor
unit.)
2. Refer to 10-6. "Check
of indoor P.C. board
and indoor fan motor".
POWER lamp
POWER lamp
4-time fl ash 5-time fl ash
Cause: Cause:
Outdoor unit
Indoor unit
• Trouble • Outdoor
of indoor power sys-
tem abnor-
unit control
system mality
Replace the Refer to
indoor elec- "How to
tronic control check
P.C. board. inverter/com-
pressor".
26
NOTE: The indoor unit does not
operate by smartphone,
refer to 10-3.2."Check of
Wi-Fi Interface".
AIR PURIFYING
lamp
2-time fl ash
cause:
indoor unit
• Trouble of AIR
PURIFYING
power control
Refer to 10-6. "Check of
AIR PURIFYING power".
Refer to outdoor unit service manual.
POWER lamp POWER lamp
7-time fl ash
6-time fl ash
Cause: Cause:
Outdoor unit Outdoor unit
• Trouble of
• Trouble of
thermistor in outdoor con-
outdoor unit trol system
Refer to Replace the
"Check of inverter P.C.
outdoor ther- board or
mistors". the outdoor
electronic
control P.C.
board.
POWER lamp
14-time fl ash
or more
Cause:
Outdoor unit
• Other ab-
normality
Check "Flow
chart of the
detailed
outdoor unit
failure mode
recall func-
tion."