Instruction For Troubleshooting - Mitsubishi Electric MLZ-KP09NA Service Manual

9-3. INSTRUCTION OF TROUBLESHOOTING
Start
Indoor unit
Indoor unit operates.
operates.
Outdoor unit does not
Outdoor unit
operate normally.
does not
operate.
Outdoor unit
Outdoor unit
operates only
does not
in Test Run operate
operation.
even in
1
Test Run
operation.
1
Refer to
Check room
"How to check
temperature
inverter/
thermistor.
compressor".
Refer to 9-7.
"TEST POINT
DIAGRAM AND
VOLTAGE".
Left lamp
Left lamp
Left lamp
2-time blink
Blink on and off
3-time blink
at 0.5-second Cause:
Cause:
Indoor unit
intervals
Indoor unit
• Trouble of
Cause:
• Trouble of
Indoor/ room temp-
indoor fan
erature/
Outdoor unit
motor
indoor coil
• Mis-wiring
or trouble thermistor
of serial signal
Refer to 9-6.
Check room
Refer to 9-6.
"Check of
temperature
"How to
indoor fan
thermistor
check
motor".
and indoor
miswiring
coil thermis-
and serial
tor.
signal error
Refer to 9-7.
(when
"Test point
outdoor unit
diagram and
does not work)".
voltage".
OBH802A
Indoor unit
does not receive
the signal from
remote controller.
Indoor unit
Unit does not
operates, when
operate
EMERGENCY
normal
OPERATION
operation in
switch is pressed.
COOL or
HEAT mode.
Refer to 9-6.
Refer to
"Check of
"Check of
remote controller,
R.V. coil".
receiver P.C.
board and
indoor electronic
control P.C.
board".
Left lamp
Left lamp
4-time blink 5-time blink
Cause:
Cause:
Indoor unit
Outdoor unit
• Trouble of
• Outdoor
indoor unit power
control
system
system
abnormality
Replace the Refer to
"How to check
indoor
the inverter/
electronic
control compressor".
P.C. board.
sandium.com
OPERATION INDICATOR
lamp on the indoor unit is
blinking on and off.
If blinking of OPERATION
Indoor unit
INDICATOR lamp cannot be
does not operate,
checked, it can be checked with
when
failure mode recall function.
EMERGENCY
OPERATION
switch is pressed.
1
"Test Run operation" means the
operation within 30 minutes after
EMERGENCY OPERATION switch
is pressed.
1. Check indoor/outdoor
connecting wire.
(Check if the power
is supplied to the
Refer to outdoor unit service manual.
indoor unit.)
2. Refer to 9-6.
"Check of indoor
electronic control
P.C. board and indoor
fan motor".
Left lamp
Left lamp
7-time blink
6-time blink
Cause:
Cause:
Outdoor unit
Outdoor unit
• Trouble of
• Trouble of
outdoor
thermistor
control
in outdoor
system
unit
Refer to Replace the
"Check of inverter P.C.
outdoor board or
thermistors". the outdoor
electronic
control P.C.
board.
25
Left lamp Left lamp
9-time blink 14-time blink
Cause: or more
Indoor unit Cause:
• Trouble of Outdoor unit
float sensor • Other
or drain abnormality
pump • Check the
stop valve.
Refer to 9-6. Check the Check
"Check of drain pump. "Flow chart of
float sensor". the detailed
outdoor unit
failure mode
recall function."