This air conditioner can memorize the abnormal condition which has occurred once.
Even though LED indication listed on the troubleshooting check table (13-4) disappears, the memorized failure details can be recalled.
This mode is very useful when the unit needs to be repaired for the abnormality which doesn’t recur.
1. Type of failure mode recall function
There are 2 types in failure mode recall function as shown below.
Indoor and outdoor unit failure mode recall function
With this function, failure mode of indoor unit and a part of failure mode of outdoor unit can be recalled.
The details of outdoor unit failure mode recall function
With this function, more detailed failure mode of outdoor unit can be recalled.
Refer to the service manual of indoor unit for how to recall the failure mode and the details of indoor unit failure mode.
The outdoor unit failure mode is indicated by the operation indicator lamp on the indoor unit and the LED of outdoor unit.
See "13-2.2. Outdoor unit failure mode table".
E1
E2
E2 E1
Abnormal point
(Failure mode / protection) Condition Correspondence Indoor/outdoor
unit failure mode recall function LED indication
(Outdoor P.C. board) LED 1 LED 2 Upper or left lamp of
OPERATION INDICATOR lamp (Indoor unit) OFF 2-time flash
3-time flash
4-time flash
5-time flash
6-time flash
7-time flash
8-time flash
Lighting Lighting Lighting Lighting
Lighting Once Lighting Once Lighting Twice Lighting 3 times Lighting 4 times
Lighting 9 times Once Goes out
Lighting Lighting
Lighting Lighting
3 times Goes out 4 times Goes
out
Lighting Lighting Lighting Lighting
Lighting 5 times 9-time flash
10-time flash
• Check the connection of the compressor connecting wire.
• Refer to 13-6.
"How to check inverter/compressor".
• Check the stop valve.
• Replace the outdoor electronic control P.C. board.
• Check refrigerant circuit and refrigerant amount.
• Refer to 13-6. "Check of LEV".
• Refer to 13-6. "Check of outdoor fan motor".
• Replace the outdoor electronic control P.C. board.
• Check refrigerant circuit and refrigerant amount.
• Refer to 13-6. "Check of LEV".
• Reconnect compressor connector.
• Refer to 13-6. "How to check inverter/
compressor".
• Check the stop valve.
• Check refrigerant circuit and refrigerant amount.
• Check the stop valve.
• Check around outdoor unit.
• Check outdoor unit air passage.
• Refer to 13-6. "Check of outdoor fan motor".
• Refer to 13-6. "Check of outdoor thermistors".
• Refer to 13-6. "Check of outdoor thermistors".
Overcurrent protection stop is continuously performed three times within 1 minute after the compressor gets started.
Thermistor shorts or opens during compressor running.
23 A (MXZ-2A30VA- , MXZ-2A40VA, MXZ-2A52VA)/ 14 A (MXZ-2A30VA- ) current flows into intelligent power module.
Discharge temperature exceeds 116°C during operation.
Compressor can restart if discharge temperature thermistor reads 100°C or less 3 minutes later.
The outdoor heat exchanger temperature exceeds 70°C during cooling or the indoor gas pipe temperature exceeds 70°C during heating.
The fin temperature exceeds 90°C during operation.
The P.C. board temperature exceeds 78°C during operation.
Failure occurs continuously three times within 30 seconds after the fan gets started.
Nonvolatile memory data cannot be read properly.
Outdoor power system
Discharge temperature thermistor
Defrost thermistor
Ambient temperature thermistor Fin temperature thermistor P.C. board temperature thermistor
Outdoor heat exchanger temperature thermistor Overcurrent
Discharge temperature
High pressure
Fin temperature
P.C. board temperature
Outdoor fan motor
Nonvolatile memory data
Discharge temperature None (Normal)
Compressor Twice
9 times Goes
out
Goes out
The possibility of intercepting the overcurrent by the compressor lock is high.
The compressor doesn't synchronize with the operating power.
• Check the connection of the compressor connecting wire.
• Refer to 13-6. "How to check inverter/
compressor".
The frequency of the compressor is kept 68 Hz (MXZ-2A30VA, MXZ- 2A40VA- )/ 80Hz (MXZ-2A40VA- , MXZ-2A52VA) or more and the discharge temperature is kept under 50°C (COOL mode)/40°C (HEAT mode) for more than 40 minutes.
NOTE: Blinking patterns of this mode differ from the ones of Troubleshooting check table (13-4).
2. Outdoor unit failure mode table MXZ-2A
11-time flash
15-time flash
• Replace the power board.
• Replace the power board.
A short or open circuit is detected in the current sensor
during compressor operating.
The bus-bar voltage exceeds 430 V or falls to 50 V or below during compressor operating.
Current sensor
Bus-bar voltage
LEV for drain
8 times Goes out 6 times Goes
out
The indoor unit detects any abnormalities in the LEV for drain.
Lighting Lighting 14-time flash
• Refer to 13-6. "Check of LEV".
• Check the drain pump of the indoor unit.
• Refer to 13-6. "How to check inverter/
compressor".
Power module There is a high possibility that the
power module is out of order.
7 times Goes out
12 times Stop valve
(Closed valve)
Closed valve is detected by compressor current.
(MXZ-2A30VA, MXZ-2A40VA - )
• Check the stop valve.
E2 Lighting
Abnormal point
(Failure mode / protection) Condition Correspondence Indoor/outdoor
unit failure mode recall function LED indication
(Outdoor P.C. board) LED 1 LED 2 Upper or left lamp of
OPERATION INDICATOR lamp (Indoor unit)
NOTE: Blinking patterns of this mode differ from the ones of Troubleshooting check table (13-4).
The frequency of the compressor is kept 80Hz or more and the discharge temperature is kept under
50°C (COOL mode)/40°C (HEAT mode) for more than 40 minutes.
Abnormal point
(Failure mode / protection) Condition Correspondence Indoor/outdoor
unit failure mode recall function LED indication
(Outdoor P.C. board) LED 1 LED 2
E1 E1 E1 E2
E1 E2 E1 E2
E3 E3 E3 OFF
2-time flash
3-time flash
4-time flash
5-time flash
6-time flash
7-time flash
8-time flash
Lighting Lighting Lighting Lighting
Lighting Once Lighting Once Lighting Twice Lighting 3 times Lighting 4 times
Lighting 9 times
Once Goes out
Lighting Lighting
Lighting Lighting
3 times Goes out 4 times Goes
out
Lighting Lighting Lighting Lighting
Lighting 5 times 9-time flash
10-time flash
• Replace the outdoor electronic control P.C. board.
• Replace the outdoor electronic control P.C. board.
• Check refrigerant circuit and refrigerant amount.
• Refer to 13-6. "Check of LEV".
• Reconnect compressor connector.
• Refer to 13-6. "How to check inverter/
compressor".
• Check the stop valve.
• Check refrigerant circuit and refrigerant amount.
• Check the stop valve.
• Refer to 13-6. "Check of outdoor fan motor".
• Check refrigerant circuit and refrigerant amount.
• Refer to 13-6. "Check of LEV".
• Check around outdoor unit.
• Check outdoor unit air passage.
• Refer to 13-6. "Check of outdoor fan motor".
• Check the connection of the compressor connecting wire.
• Refer to 13-6.
"How to check inverter/compressor".
• Check the stop valve.
• Refer to 13-6. "Check of outdoor thermistors".
• Refer to 13-6. "Check of outdoor thermistors".
Overcurrent protection stop is continuously performed three times within 1 minute after the compressor gets started, or converter protection stop or bus-bar voltage protection stop is continuously performed three times within 3 minutes after start-up.
Thermistor shorts or opens during compressor running.
28A current flows into intelligent power module.
Discharge temperature exceeds 116°C during operation.
Compressor can restart if discharge temperature thermistor reads 100°C or less 3 minutes later.
High-pressure is detected with the high-pressure switch (HPS) during operation.
(MXZ-4A80VA, MXZ-5A100VA) The outdoor heat exchanger temperature exceeds 70°C during cooling or the indoor gas pipe temperature exceeds 70°C during heating.
The fin temperature exceeds 89°C during operation.
The P.C. board temperature exceeds 73°C (MXZ-3A54VA, MXZ-4A71VA)/
87°C (MXZ-4A80VA, MXZ-5A100VA) during operation.
Failure occurs continuously three times within 30 seconds after the fan gets started.
Nonvolatile memory data cannot be read properly.
Outdoor power system
Discharge temperature thermistor
Defrost thermistor
Ambient temperature thermistor Fin temperature thermistor P.C. board temperature thermistor
Outdoor heat exchanger temperature thermistor
Overcurrent
Discharge temperature
High pressure
Fin temperature P.C. board temperature
Outdoor fan motor
Nonvolatile memory data
Discharge temperature Gas pipe temperature thermistor A
Lighting 10 times Gas pipe temperature
thermistor B
Lighting 11 times Gas pipe temperature
thermistor C
Lighting 12 times Gas pipe temperature
thermistor D
Lighting 13 times
A short or open circuit is detected in the thermistor during cooling.
(A,B,C : MXZ-3A54VA- , , MXZ-4A71VA- , ,
MXZ-4A80VA- ) (D : MXZ-4A71VA- , ,
MXZ-4A80VA- ) None (Normal)
Upper or left lamp of OPERATION INDICATOR lamp (Indoor unit)
NOTE: Blinking patterns of this mode differ from the ones of Troubleshooting check table (13-4).
MXZ-3A/4A/5A
Operation start
Check the outdoor unit LED indicator.
Refer to 13-6.
"Check of power supply".
• When cooling, dew drops in the non-operating indoor unit.
Check of mispiping
• Indoor unit serial signal error
Refer to 13-6.
"How to check miswiring and serial signal error".
• COOL or HEAT operation only Refer to 13-6.
"Check of R.V. coil".
• When cooling, room does not cool.
Refer to 13-6.
"How to check of inverter/
compressor".
• When cooling, heat exchanger of non-operating indoor unit frosts.
•When heating, non- operating indoor unit gets warm.
Refer to 13-6.
"Check of LEV".
• When heating, room does not get warm.
Refer to 13-6.
"How to check of inverter/compressor".
Check mispiping, shortage of capacity
Refer to 13-4.
"Troubleshooting check table".
Both LED 1 and LED 2 are lighting.
LED 1 or LED 2 has blinked.
Both LED 1 and LED 2 are OFF.