Mitsubishi Electric MUZ-EF25VE-E1 Service Manual page 35

3. Outdoor unit failure mode table
The left
lamp of
OPERATION Abnormal point
INDICATOR (Failure mode/protection)
lamp
(Indoor unit)
OFF None (Normal)
1-time fl ash Indoor/outdoor
2.5 seconds communication, receiving
OFF error
Indoor/outdoor
communication, receiving
error
2-time fl ash Outdoor power system
2.5 seconds
OFF
3-time fl ash Discharge temperature
2.5 seconds thermistor
OFF
Defrost thermistor
Fin temperature thermistor
P.C. board temperature
thermistor
Ambient temperature
thermistor
Outdoor heat exchanger
temperature thermistor
4-time fl ash Overcurrent
2.5 seconds
OFF
Compressor synchronous
abnormality (Compressor
start-up failure protection)
5-time fl ash Discharge temperature
2.5 seconds
OFF
6-time fl ash High pressure
2.5 seconds
OFF
7-time fl ash Fin temperature/ P.C. board
2.5 seconds temperature
OFF
8-time fl ash Outdoor fan motor
2.5 seconds
OFF
9-time fl ash Nonvolatile memory data
2.5 seconds
OFF
Power module
NOTE: Blinking patterns of this mode differ from the ones of Troubleshooting check table (11-3.).
OBH590G
LED indication
(Outdoor P.C. board)
—
Any signals from the inverter P.C.
— board cannot be received normally for
3 minutes.
Although the inverter P.C. board sends
— signal "0", signal "1" has been received
30 consecutive times.
Overcurrent protection cut-out
operates 3 consecutive times within
1 minute after the compressor gets
—
started.
1-time fl ash every Thermistor shorts or opens during
2.5 seconds compressor running.
3-time fl ash
2.5 seconds OFF
4-time fl ash
2.5 seconds OFF
2-time fl ash
2.5 seconds OFF
—
11-time fl ash Large current fl ows into intelligent
2.5 seconds OFF power module.
12-time fl ash Waveform of compressor current is
2.5 seconds OFF distorted.
Temperature of discharge temperature
thermistor exceeds 116°C, compressor
stops.
—
Compressor can restart if discharge
temperature thermistor reads 100°C or
less 3 minutes later.
Temperature indoor coil thermistor
exceeds 70°C in HEAT mode.
—
Temperature defrost thermistor
exceeds 70°C in COOL mode.
7-time fl ash Temperature of fi n temperature
2.5 seconds OFF thermistor on the inverter P.C. board
exceeds 75 ~ 86°C, or temperature of
P.C. board temperature thermistor on
the inverter P.C. board exceeds 72 ~
85°C.
Outdoor fan has stopped 3 times in a
row within 30 seconds after outdoor
— fan start-up.
5-time fl ash Nonvolatile memory data cannot be
2.5 seconds OFF read properly.
6-time fl ash The interface short circuit occurs in the
2.5 seconds OFF output of the intelligent power module
(IC700).
The compressor winding shorts circuit.
Condition
—
•Refer to 11-5.
to check miswiring and
serial signal error.
•Refer to 11-5.
to check miswiring and
serial signal error.
• Reconnect
connectors.
• Refer to 11-5.
to check inverter/
compressor".
• Check the stop valve.
• Refer to 11-5.
"Check of outdoor
thermistors".
Defective outdoor
thermistors can be
identifi ed by checking
the blinking pattern of
LED.
• Reconnect
compressor connector.
• Refer to 11-5. "How
to check inverter/
compressor".
• Check the stop valve.
• Reconnect
compressor connector.
• Refer to 11-5. "How
to check inverter/
compressor".
• Check the refrigerant
circuit and the
refrigerant amount.
• Refer to 11-5. "Check
of LEV".
• Check the refrigerant
circuit and the
refrigerant amount.
• Check the stop valve.
• Check the around
outdoor unit.
• Check the outdoor unit
air passage.
• Refer to 11-5. "Check
of outdoor fan motor".
• Refer to 11-5. "Check
of outdoor fan motor".
Refer to 11-5. "Check
of inverter P.C. board".
• Replace the inverter
P.C. board.
• Refer to 11-5.
to check inverter/
compressor".
35
Indoor/outdoor
unit failure
Remedy
mode recall
recall function
function
— —
How
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"How
Outdoor unit
failure mode
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