Mitsubishi Electric R410A Service Handbook page 274

[8-9 Troubleshooting Inverter Problems (TLMU) ]
Error display/failure condition
[1] Inverter related errors
4250, 4255, 4256, 4220, 4225, 4226, 4230, 4240, 4260,
5301, 5305, 5306, 0403
[2] Main power breaker trip
[3] Main power earth leakage breaker trip
[4] Only the compressor does not operate.
[5] The compressor vibrates violently at all times or makes
an abnormal sound.
[6] Compressor rotation speed does not reach the specified
speed.
[7] Only the fan motor does not operate.
[8] The fan motor shakes violently at all times or makes an
abnormal sound.
[9] Noise is picked up by the peripheral device
[10] Sudden malfunction (as a result of external noise.)
HWE14080
Measure/inspection item
Implement solutions that correspond to the error codes or preliminary error codes.[7-
1 Error Code and Preliminary Error Code Lists](page 151)
<1> Check the breaker capacity.
<2> Check whether the electrical system is short-circuited or ground-faulted.
<3> If <1> or <2> is not the cause of the problem, refer to the following page(s). [8-
9-11 Solutions for the Main No-Fuse Breaker Trip](page 271)
<1> Check the earth leakage breaker capacity and the sensitivity current.
<2> Meg failure for electrical system other than the inverter
<3> If <1> or <2> is not the cause of the problem, refer to the following page(s). [8-
9-11 Solutions for the Main No-Fuse Breaker Trip](page 271)
Check the inverter frequency on the LED monitor. If the frequency indicates that the
units are in operation, refer to the following page(s). [8-9-5 Checking the Inverter for
Damage during Compressor Operation](page 268)
Refer to the following page(s). [8-9-5 Checking the Inverter for Damage during Com-
pressor Operation](page 268)
<1> Check for problems with compressor current and heatsink temperature. Refer
to the following page(s). [7-1-1 Inverter Protection Level Table](page 155)
<2> Check for imbalance in power supply voltage. *Approximate target: 3% or less.
Check the inverter frequency on the LED monitor. If the frequency indicates that the
units are in operation, refer to the following page(s).
[8-9-7 Checking the Fan Board Error Detection Circuit at No Load](page 268)
[8-9-8 Checking the Fan Inverter for Damage at No Load](page 269)
[8-9-9 Checking the Fan Inverter for Damage with Load](page 270)
Check the inverter frequency on the LED monitor. If the frequency indicates that the
units are in operation, refer to the following page(s).
[8-9-7 Checking the Fan Board Error Detection Circuit at No Load](page 268)
[8-9-8 Checking the Fan Inverter for Damage at No Load](page 269)
[8-9-9 Checking the Fan Inverter for Damage with Load](page 270)
<1> Check that power supply wiring of the peripheral device does not run close to
the power supply wiring of the outdoor unit.
<2> Check that the inverter output wiring is not in close contact with the power sup-
ply wiring and the transmission lines.
<3> Check that the shielded wire is used as the transmission line when it is required,
and check that the grounding work is performed properly on the shielded wire.
<4> Meg failure for electrical system other than the inverter
<5> Attach a ferrite core to the inverter output wiring. (Contact the factory for details
of the service part settings.)
<6> Provide separate power supply to the air conditioner and other electric applianc-
es.
<7> If the problem suddenly appeared, inverter output may have had a ground fault.
For details, refer to the following page(s). [8-9-5 Checking the Inverter for Dam-
age during Compressor Operation](page 268)
*Contact the factory for cases other than those listed above.
<1> Check that the grounding work is performed properly.
<2>Check that the shielded wire is used as the transmission line when it is required,
and check that the grounding work is performed properly on the shielded wire.
<3>Check that neither the transmission line nor the external connection wiring does
not run close to another power supply system or does not run through the same
conduit pipe.
* Contact the factory for cases other than those listed above.
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