Daikin FTKB09AXVJU Service Manual page 64

Description IPM ABNORMALITY
Possible Root 1. Over current due to defective power transistor.
cause 2. Over current due to wrong internal wiring.
3. Over current due to abnormal supply voltage.
4. Over current due to defective PCB.
5. Error detection due to defective PCB.
6. Over- current due to closed stop valve.
7. Over current due to compressor failure.
8. Over current due to poor installation condition.
9. Connection between main board and IPM board is not properly connect.
Troubleshooting
*Remark:
Refer to Appendix A for installation condition check. (Page 71, item 6.6)
Check the installation condition.
Stop valve
fully open?
Yes
Turn off the power and turn it on
again to start the system. See if
the same error occurs.
Error again?
Yes
Turn off power and disconnect
the harnesses U, V and W.
Check with the inverter analyzer.
Any LED off?
No
Turn off the power and
reconnect the harnesses. Turn
on the power again and start
operation.
Check the power supply voltage.
Voltage as rated?
Yes
L5
No
No
Yes
No
Service Diagnosis
Fully open the stop valve.
Monitor the power supply
voltage and suction
pressures, and other factors
for a long term.
Correct the power supply or
replace the outdoor unit PCB.
Correct the power supply.
Replace the compressor.
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