Mitsubishi Electric MSZ-D30NA Service Manual page 22

9-3. INSTRUCTION OF TROUBLESHOOTING
Start
Indoor unit operates.
Outdoor unit does not
operate.
Outdoor unit Outdoor unit
operates only does not
in Test Run operate even
operation. * in Test Run
operation. *
Check room Refer to "How
temperature to check
thermistor. inverter/
Refer to 9-7. compressor".
"Test point
diagram and
voltage".
Left lamp Left lamp
Blink on and 2-time blink
off at 0.5-sec- Cause:
ond intervals Indoor unit
Cause: • Trouble of
Indoor/Outdoor room tem-
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".
OBH501D
Indoor unit operates. Indoor unit does not
Outdoor unit does not receive the signal from
operate normally. remote controller.
Unit does
Indoor unit oper-
not operate
ates, when the
normally in
emergency oper-
COOL or
ation switch is
HEAT mode
pressed.
operation.
Refer to
Refer to 9-6.
"Check of
"Check of
R.V. coil".
remote controller
and receiver
P.C. board".
Left lamp Left lamp
3-time blink 4-time blink
Cause: Cause:
Indoor unit Indoor unit
• Trouble of • Trouble of
indoor fan indoor unit
motor control sys-
tem
Refer to 9-6. Replace the
"Check of indoor elec-
indoor fan tronic control
motor". P.C. board.
OPERATION INDICATOR
lamp on the indoor unit is
blinking on and off.
Indoor unit does
not operate,
when the emer-
gency operation
switch is pressed.
1. Check indoor/outdoor
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 blink
5-time blink
Cause: Cause:
Outdoor unit Outdoor unit
• Trouble of
• Outdoor
power sys- thermistor in
tem abnor- outdoor unit
mality
Refer to "How Refer to
to check "Check of
inverter/com- outdoor
pressor". thermistors".
22
If blinking of OPERATION
INDICATOR lamp cannot be
checked, it can be checked with
failure mode recall function.
* "Test Run operation" means the
operation within 30 minutes after
the emergency operation switch
is pressed.
Refer to outdoor unit service manual.
Left lamp Left lamp
7-time blink 14-time blink
Cause: Cause:
Outdoor unit Outdoor unit
• Trouble of • Other
outdoor con- abnormality
trol system
Replace the Check "Flow
inverter P.C. chart of the
board or the detailed out-
outdoor elec- door unit fail-
tronic control ure mode
P.C. board. recall func-
tion."