Mitsubishi Electric M-SERIES, Installation Manual

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97
MITSUBISHI ELECTRIC / DIAGNOSTIC
Lit
Blinking
Not lit
NO. ABNORMAL POINT OPERATION INDICATOR LAMP SYMPTOM CONDITION REMEDY
1
Connection error
or serial signal
Left lamp blinks.
0.5-second ON
0.5-second OFF
Indoor unit and
outdoor unit do not
operate
The serial signal from the
outdoor unit is not received for
6 minutes.
The indoor unit is connected
to a low-stand-by-power model
after once connected to a mom-
low-standby-power model.
Refer to 10-6.
”How to check miswiring and
serial signal error”
2
Indoor coil thermistor
Left lamp blinks.
2-time blink
2.5-second OFF
The indoor coil or the room
temperature thermistor is short
or open circuit.
Refer to the characteristics of
indoor coil thermistor, and the
room temperature thermistor
(10-7.).
Room temperature
thermistor
3 Indoor fan motor
Left lamp blinks.
3-time blink
2.5-second OFF
The rotational frequency
feedback signal is not emitted
during the indoor fan operation.
Refer to 10-6.
”Check of indoor fan motor”.
4 Indoor control system
Left lamp blinks.
4-time blink
2.5-second OFF
Is cannot property read data in
the nonvolatie memory of the
indoor electronic control P.C.
board.
Replace the indoor electronic
control P.C. board.
5 Outdoor power system
Left lamp blinks.
5-time blink
2.5-second OFF
It consecutively occurs 3 times
that the compressor stops for
overcurrent protection or start-
up falure protection within 1
minute after start-up.
Refer to
“How to check of inverter/
compressor”.Refer to outdoor unit
service manual
Check the stop valve
6 Outdoor thermistors
Left lamp blinks.
6-time blink
2.5-second
OFF
The outdoor thermistors short
or open circuit during the
compressor operation.
Refer to “Check of outdoor
thermistor”.Refer to outdoor unit
service manual.
7 Outdoor control system
Left lamp blinks.
7-time blink
2.5-se-
cond OFF
It cannot property read data
in the nonvolatie memory of
the inverter P.C. board or the
outdoor electronic control P.C.
board.
Replace the inverter P.C. boardor
the outdoor electronic control P.C.
board.
Refer to outdoor unit
servicemanual.
8 Other abnormalty
Left lamp blinks.
14-time blink or more
2.5-second OFF
An abnormalty other than above
mentioned is detected.
Check the stop valve.
Check the 4-way valve.
Confirm the abnormality indetail
using the failure mode recall
function for outdoor unit.
9 Outdoor control system
Left lamp lights up
Outdoor unit does
not operate
It cannot property read data
in the nonvolatie 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.
LEGENDA
TROUBLESHOOTING TAB