Mitsubishi Electric Mr.Slim MUZ-FD09NA Service Manual page 19

3. Outdoor unit failure mode table
POWER lamp Abnormal point
(Indoor unit) (Failure mode / protection)
OFF None (Normal)
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
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
10-time fl ash Discharge temperature
2.5 seconds
OFF
11-time fl ash DC voltage
2.5 seconds
OFF
Each phase current of
compressor
12-time fl ash Overcurrent Compressor open-
2.5 seconds phase
OFF
14-time fl ash Stop valve (Closed valve)
2.5 seconds
OFF
NOTE: Blinking patterns of this mode differ from the ones of Troubleshooting check table (10-3.).
LED indication
(Outdoor P.C. board)
—
Overcurrent protection stop is
continuously performed 3 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 241°F (116°C),
compressor stops.
Compressor can restart if discharge
—
temperature thermistor reads 212°F
(100°C) or less 3 minutes later.
Temperature of indoor coil thermistor
exceeds 158°F (70°C) in HEAT mode.
Temperature of defrost thermistor
—
exceeds 158°F (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 167 ~ 176°F (75 ~ 80°C), or
temperature of P.C. board temperature
thermistor on the inverter P.C. board
exceeds 158 ~ 167°F (70 ~ 75°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.
Temperature of discharge temperature
thermistor has been 122°F (50°C) or
— less for 20 minutes.
8-time fl ash DC voltage of inverter cannot be
2.5 seconds OFF detected normally.
9-time fl ash Each phase current of compressor
2.5 seconds OFF cannot be detected normally.
10-time fl ash Large current fl ows into intelligent
2.5 seconds OFF power module (IPM).
The open-phase operation of
compressor is detected.
The interphase short out occurs in the
output of the intelligent power module
(IPM).
The compressor winding shorts out.
14-time fl ash Closed valve is detected by compressor
2.5 seconds OFF current.
Condition
—
• Reconnect connectors.
• Refer to 10-5.
to check inverter/
compressor".
• Check stop valve.
• Refer to 10-5. "Check
of outdoor thermistors".
Defective outdoor
thermistors can be
identifi ed by checking
the blinking pattern of
LED.
• Reconnect compressor
connector.
• Refer to 10-5. "How
to check inverter/
compressor".
• Check stop valve.
• Reconnect compressor
connector.
• Refer to 10-5. "How
to check inverter/
compressor".
• Check refrigerant circuit
and refrigerant amount.
• Refer to 10-5. "Check
of LEV".
• Check refrigerant circuit
and refrigerant amount.
• Check stop valve.
• Check around outdoor
unit.
• Check outdoor unit air
passage.
• Refer to 10-5. "Check
of outdoor fan motor".
• Refer to 10-5. "Check
of outdoor fan motor".
Refer to 10-5. "Check
of inverter P.C. board".
• Replace the inverter
P.C. board.
• Refer to 10-5. "Check
of LEV".
• Check refrigerant circuit
and refrigerant amount.
• Refer to 10-5. "How
to check inverter/
compressor".
• Reconnect compressor
connector.
• Refer to 10-5.
to check inverter/
compressor".
• Check stop valve
19
Indoor/
outdoor unit
Correspondence
failure mode
recall function
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Outdoor unit
failure mode
recall function
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