Service manual

108
LED 1 (Red)
Lighting
LED 2 (Yellow)
Lighting
Error mode
Normal
MXZ-A18WV -
<OUTDOOR UNIT>
E1
Indication
Abnormal point Detecting method
Symptom: Outdoor unit does not operate.
Check points
LED 1
(Red)
Lighting Twice Outdoor power system
When the compressor operation has been interrupted by over current
protection continuously three times within 1 minute after start-up.
• Check the inverter/compressor.
Lighting 8 times Active filter module
When active filter module self-protection has been performed
continuously three times.
• Replace the outdoor electronic control
P.C. board.
• Replace the outdoor electronic control
P.C. board.
• Check the abnormality indication on the
indoor unit.
• Check the LEV.
Lighting 7 times Outdoor control system
Lighting Once Indoor unit and LEV
When the nonvolatile memory data cannot be read properly on the
outdoor electronic control P.C. board.
• Replace the outdoor electronic control
P.C. board.
Lighting 9 times
DC voltage sensing
circuit
When DC voltage sensing circuit detects 57V or below or 395V or above.
When the drain abnormality is detected in the indoor unit and the indoor
unit coil temperature is too low, or when any abnormality is detected in
the components of indoor unit.
LED 2
(Yellow)
Indication
Abnormal point Detecting method
Symptom: Outdoor unit repeats to stop and restart in 3 minutes
Check points
LED 1
(Red)
Lighting
High pressure protect
thermistor
When high pressure protect thermistor is short or open while
compressor is operating.
• Replace the outdoor electronic control
P.C. board.
• Check the amount of gas and the
refrigerant cycle.
• Check the outdoor unit air passage.
• Check the characteristic of the discharge
temperature thermistor.
• Check the connector. (CN662)
Lighting 3 times
Discharge temperature
thermistor
When a short or open circuit occurs in the discharge temperature
thermistor during compressor running.
Twice Goes out
Over current protection When over current is applied to the power module.
5 times Goes out
High pressure protection When high pressure protect thermistor detects 69: or more.
3 times Goes out
Discharge temperature
overheat protection
When the discharge temperature thermistor detects 116: or above.
(Protection will be released at 100: or below.)
4 times Goes out
Fin temperature
overheat protection
When the fin temperature thermistor detects 87: or above.
4 times Goes out
P.C. board temperature
overheat protection
When the P.C. board temperature thermistor detects 70: or above.
• Check the characteristic of the evaporation
temperature thermistor.
• Check the connector. (CN662)
• Check the characteristic of the high
pressure protect thermistor.
• Check the connector. (CN662)
Lighting 5 times
5 times
Evaporation temperature
thermistor
When a short or open circuit occurs in the evaporation temperature
thermistor during compressor running.
• Check the characteristic of the gas pipe
temperature A thermistor.
• Check the connector. (CN661)
Lighting 10 times
Gas pipe temperature A
thermistor
When a short or open circuit occurs in the gas pipe temperature A
thermistor during compressor running.
• Check the characteristic of the gas pipe
temperature B thermistor.
• Check the connector. (CN661)
• Check the outdoor unit air passage.
• Check the outdoor fan motor.
• Check the power module.
• Check the outdoor unit air passage.
• Check the outdoor fan motor.
• Replace the outdoor electronic control
P.C. board.
• Check the outdoor unit air passage.
• Check the outdoor fan motor.
• Check the inverter/compressor.
• Check the amount of gas.
• Check the indoor/outdoor air flow for
short cycle.
• Check the indoor unit air filter for clogging.
Gas pipe temperature B
thermistor
When a short or open circuit occurs in the gas pipe temperature B
thermistor during compressor running.
• Check the characteristic of the fin
temperature thermistor.
• Check the connector. (CN663)
Lighting 4 times
Fin temperature
thermistor
When a short or open circuit occurs in the fin temperature thermistor
during compressor running.
P.C. board temperature
thermistor
When a short or open circuit occurs in the P.C. board temperature
thermistor during compressor running.
LED 2
(Yellow)
OB307A4.qxp 03.2.19 4:11 PM Page 108