MITSUBISHI ELECTRIC MSZ-FD25VAS - Manual (Page 25)

25
No.
1
2
5
6
Symptom Operation indicator lamp Condition Correspondence
POWER lamp flashes.
0.5-second ON
0.5-second OFF
Miswiring
or serial
signal
Outdoor
power
system
Outdoor
thermistors
Outdoor
control
system
Indoor coil
thermistor
The serial signal from the outdoor unit is not
received for 6 minutes.
It consecutively occurs 3 times that the
compressor stops for overcurrent protection or
start-up failure protection within 1 minute after
start-up.
The outdoor thermistors short or open circuit
during the compressor operation.
It cannot properly read data in the nonvolatile
memory of the inverter P.C. board or the
outdoor electronic control P.C. board.
• Refer to "Check of outdoor
thermistor".
Refer to outdoor unit service
manual.
• Refer to "How to check of
inverter/compressor".
Refer to outdoor unit service
manual.
• Check the stop valve.
• Replace the inverter P.C.
board or the outdoor
electronic control P.C. board.
Refer to outdoor unit service
manual.
• Refer to 10-6. D "How to check
miswiring and serial signal
error".
3 Indoor fan
motor
7
Abnormal
point
Room
temperature
thermistor
POWER lamp flashes.
2-time flash
2.5-second OFF
The indoor coil or the room temperature
thermistor is short or open circuit.
• Refer to 10-7.the
characteristics of indoor coil
thermistor, and the room
temperature thermistor.
POWER lamp flashes.
3-time flash
2.5-second OFF
The rotational frequency feedback signal is
not emitted during the indoor fan operation. • Refer to 10-6. A "Check of
indoor fan motor".
Indoor unit
and outdoor
unit do not
operate.
POWER lamp flashes.
5-time flash
2.5-second OFF
POWER lamp flashes.
6-time flash
2.5-second OFF
Other
abnormality
An abnormality other than above mentioned is
detected.
• Check the stop valve.
• Confirm the abnormality in
detail using the failure mode
recall function for outdoor
unit. 8
4
POWER lamp flashes.
4-time flash
2.5-second OFF
Indoor
control
system It cannot properly read data in the nonvolatile
memory of the indoor electronic control P.C.
board.
• Replace the indoor electronic
control P.C. board.
Outdoor
control
system It cannot properly read data in the nonvolatile
memory of the inverter P.C. board or the
outdoor electronic control P.C. board.
• Check the blinking pattern of
the LED on the inverter P.C.
board or the outdoor
electronic
control P.C. board.
9
Outdoor unit
does not
operate.
POWER lamp lights up.
POWER lamp flashes.
7-time flash
2.5-second OFF
POWER lamp flashes.
14-time flash
2.5-second OFF
10-4. TROUBLESHOOTING CHECK TABLE
Lighted
Blinking
Not lighted
AREA R POWER CLEAN PLASMA L
Before taking measures, make sure that the symptom reappears for accurate troubleshooting.
When the indoor unit has started operation and the following detection method has detected an abnormality (the first detection
after the power ON), the indoor electronic control P.C. board turns OFF the indoor fan motor with OPERATION INDICATOR
lamp flashing.
OBH488-1.qxp 07.8.9 4:52 PM Page 25