MITSUBISHI ELECTRIC MUY-GE09NA - Manual (Page 26)

26
3. Outdoor unit failure mode table
POWER lamp
(Indoor unit)
Abnormal point
(Failure mode / protection)
LED indication
(Outdoor P.C. board)
Condition Remedy
Indoor/
outdoor unit
failure mode
recall function
Outdoor unit
failure mode
recall function
OFF None (Normal)
— — — — —
2-time fl ash
2.5 seconds
OFF
Outdoor power system
—
Overcurrent protection stop is
continuously performed 3 times within
1 minute after the compressor gets
started.
Reconnect connectors.
Refer to 10-5. "How
to check inverter/
compressor".
Check stop valve.
•
•
•
○ ○
3-time fl ash
2.5 seconds
OFF
Discharge temperature
thermistor
1-time fl ash every
2.5 seconds
Thermistor shorts or opens during
compressor running.
Refer to 10-5. "Check
of outdoor thermistors".
Defective outdoor
thermistors can be
identifi ed by checking
the blinking pattern of
LED.
•
○ ○
Defrost thermistor (MUZ)
Fin temperature thermistor 3-time fl ash
2.5 seconds OFF
P.C. board temperature
thermistor
4-time fl ash
2.5 seconds OFF
Ambient temperature
thermistor
2-time fl ash
2.5 seconds OFF
4-time fl ash
2.5 seconds
OFF
Overcurrent 11-time fl ash
2.5 seconds OFF
Large current fl ows into intelligent
power module.
Reconnect compressor
connector.
Refer to 10-5. "How
to check inverter/
compressor".
Check stop valve.
•
•
•
—
○
Compressor synchronous
abnormality (Compressor start-
up failure protection)
12-time fl ash
2.5 seconds OFF
Waveform of compressor current is
distorted.
Reconnect compressor
connector.
Refer to 10-5. "How
to check inverter/
compressor".
•
• —
○
5-time fl ash
2.5 seconds
OFF
Discharge temperature
—
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.
Check refrigerant circuit
and refrigerant amount.
Refer to 10-5. "Check
of LEV".
•
•
—
○
6-time fl ash
2.5 seconds
OFF
High pressure
(MUZ)
—
Temperature of indoor coil thermistor
exceeds 158°F (70°C) in HEAT mode.
Temperature of outdoor heat exchanger
temperature thermistor exceeds 158°F
(70°C) in COOL mode.
Check refrigerant circuit
and refrigerant amount.
Check stop valve.
•
• —
○
7-time fl ash
2.5 seconds
OFF
Fin temperature/ P.C. board
temperature
7-time fl ash
2.5 seconds OFF
Temperature of fi n temperature
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).
Check around outdoor
unit.
Check outdoor unit air
passage.
Refer to 10-5. "Check
of outdoor fan motor".
•
•
•
—
○
8-time fl ash
2.5 seconds
OFF
Outdoor fan motor
—
Outdoor fan has stopped 3 times in a
row within 30 seconds after outdoor fan
start-up.
Refer to 10-5. "Check
of outdoor fan motor".
Refer to 10-5. "Check
of inverter P.C. board".
•
—
○
9-time fl ash
2.5 seconds
OFF
Nonvolatile memory data 5-time fl ash
2.5 seconds OFF
Nonvolatile memory data cannot be
read properly.
Replace the inverter
P.C. board.
•
○ ○
10-time fl ash
2.5 seconds
OFF
Discharge temperature
—
Temperature of discharge temperature
thermistor has been 122°F (50°C) or
less for 20 minutes.
Refer to 10-5. "Check
of LEV".
Check refrigerant circuit
and refrigerant amount.
•
•
—
○
11-time fl ash
2.5 seconds
OFF
DC voltage 8-time fl ash
2.5 seconds OFF
DC voltage of inverter cannot be
detected normally.
Refer to 10-5. "How
to check inverter/
compressor".
•
—
○
Each phase current of
compressor
9-time fl ash
2.5 seconds OFF
Each phase current of compressor
cannot be detected normally.
12-time fl ash
2.5 seconds
OFF
Overcurrent Compressor open-
phase
10-time fl ash
2.5 seconds OFF
Large current fl ows into intelligent
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.
Reconnect compressor
connector.
Refer to 10-5. "How
to check inverter/
compressor".
•
•
—
○
14-time fl ash
2.5 seconds
OFF
Stop valve (Closed valve) 14-time fl ash
2.5 seconds OFF
Closed valve is detected by compressor
current.
Check stop valve •
○ ○
NOTE : Blinking patterns of this mode differ from the ones of Troubleshooting check table (10-3.).