Mitsubishi Electric MXZ-2A20NA-1 Service Manual page 41

2. Outdoor unit failure mode table
The left lamp of
Abnormal point
OPERATION INDICATOR
(Failure mode / protection)
lamp (Indoor unit)
None (Normal)
OFF
Outdoor power system
2-time flash
3-time flash Discharge temperature
thermistor
Defrost thermistor
Ambient temperature thermistor
Fin temperature thermistor
P.C. board temperature
thermistor
Outdoor heat exchanger
temperature thermistor
Gas pipe temperature
thermistor A
Gas pipe temperature
thermistor B
Gas pipe temperature
thermistor C
Overcurrent
4-time flash
5-time flash Discharge temperature
High pressure
6-time flash
Fin temperature
7-time flash
P.C. board temperature
8-time flash
Outdoor fan motor
9-time flash Nonvolatile memory data
Discharge temperature
10-time flash
NOTE : Blinking patterns of this mode differ from the ones of Troubleshooting check table (11-4.).
LED indication
Condition
(Outdoor P.C. board)
LED 1 LED 2
- -
Lighting Lighting When overcurrent protection stop is
continuously performed three times
within 1 minute after the compressor
gets started, or when converter
protection stop or bus-bar voltage
protection stop is continuously
performed three times within 3
minutes after start-up.
Lighting Once When thermistor shorts or opens
during compressor running.
Lighting Once
Lighting Twice
Lighting 3 times
Lighting 4 times
Lighting 9 times
Lighting 10 times When a short or open circuit is
detected in the thermistor during
cooling.
Lighting 11 times
(A,B: MXZ-2A20NA, MXZ-3A30NA)
(C : MXZ-3A30NA)
Lighting 12 times
Once Goes out When 28A current flow into intelligent
power module.
When discharge temperature exceeds
Lighting Lighting
240.8˚F during operation.
Compressor can restart if discharge
temperature thermistor reads 212˚F or
less 3 minutes later.
Lighting Lighting
When high-pressure is detected
with the high-pressure switch
(HPS) during operation. (MXZ-3A30)
When the outdoor heat exchanger
temperature exceeds 158˚F
during cooling or the indoor gas
pipe temperature exceeds 158˚F
during heating.
3 times
Goes
When the fin temperature exceeds
out
188.6˚F during operation.
4 times Goes When the P.C. board temperature
out exceeds 158˚F during operation.
Lighting Lighting
When failure occurs continuously
three times within 30 seconds after
the fan gets started.
Lighting 5 times
When nonvolatile memory data
cannot be read properly.
Lighting Lighting
When the frequency of the
compressor is kept 80Hz or
more and the discharge
temperature is kept under 102.2˚F
for more than 20 minutes.
41
Indoor/outdoor
Correspondence
unit failure mode
recall function
• Check the connection
of the compressor
connecting wire.
• Refer to 11-6.E
"How to check
inverter / compressor".
• Check the stop valve.
• Refer to 11-6.F "Check
of outdoor thermistors".
• Replace the outdoor
electronic control
P.C. board.
• Refer to 11-6.F "Check
of outdoor thermistors".
• Reconnect compressor
connector.
• Refer to 11-6.E "How to
check inverter/
compressor".
• Check the stop valve.
•Check refrigerant circuit
and refrigerant amount.
• Refer to 11-6.D "Check
of LEV".
•Check refrigerant circuit
and refrigerant amount.
• Check the stop valve.
• Check around outdoor
unit.
• Check outdoor unit air
passage.
• Refer to 11-6.G "Check
of outdoor fan motor".
• Refer to 11-6.G "Check
of outdoor fan motor".
• Replace the outdoor
electronic control
P.C. board.
•Check refrigerant circuit
and refrigerant amount.
• Refer to 11-6.D "Check
of LEV".