Troubleshooting Tab - Mitsubishi Electric M Series Installation Manual

TROUBLESHOOTING TAB

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