Mitsubishi Electric MXZ-2B30VA, Service Manual

Page: 68 / 204

68
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 Remedy
Indoor/outdoor
unit failure mode
recall function
LED indication
(Outdoor P.C. board)
LED 1 LED 2
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 11-6.
"Check
of LEV".
• Reconnect compressor
connector.
• Refer to 11-6.
"How to
check inverter/
compressor".
• Check the stop valve.
• Check refrigerant circuit
and refrigerant amount.
• Check the stop valve.
• Refer to 11-6. "Check
of outdoor fan motor".
• Check refrigerant circuit
and refrigerant amount.
• Refer to 11-6.
"Check
of LEV".
• Check around outdoor
unit.
• Check outdoor unit air
passage.
• Refer to 11-6.
"Check
of outdoor fan motor".
• Check the connection
of the compressor
connecting wire.
• Refer to 11-6.
"How to check
inverter/compressor".
• Check the stop valve.
• Refer to 11-6. "Check
of outdoor thermistors".
• Refer to 11-6. "Check
of outdoor thermistors". 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-3B68/4B71/4B80/5B100VA
)
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-3B54/3B68/4B71VA
)/
87°C (
MXZ-4B80/5B100VA
)
during operation.
Failure occurs 3 consecutive 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
Overcurrent
Discharge temperature
High pressure
Fin temperature
P.C. board temperature
Outdoor fan motor
Nonvolatile memory data
Discharge temperature
None (Normal)
Upper or left lamp of
OPERATION INDICATOR
lamp (Indoor unit)
Outdoor heat exchanger
temperature thermistor
Overcurrent protection cut-out
operates 3 consecutive times within
1 minute after the compressor gets
started, or converter protection cut-out
or bus-bar voltage protection cut-out
operates 3 consecutive times within 3
minutes after start-up.
NOTE : Blinking patterns of this mode differ from the ones of Troubleshooting check table (11-4).
MXZ-3B/4B/5B
OBH554D