Troubleshooting SiBE12-712C240 Service Diagnosis4.22 Over-voltage Detection / Low-voltage DetectionRemoteControllerDisplayU2Method ofMalfunctionDetectionAn abnormal voltage rise (or drop) is detected by checking the detection circuit or DC voltagedetection circuit.MalfunctionDecisionConditions An over-voltage signal is fed from the over-voltage detection circuit to the microcomputer, orthe voltage being detected by the DC voltage detection circuit is judged to be below 150V for0.1 second. The system will be shut down if the error occurs 255 times. Clearing condition: Continuous run for about 60 minutes (normal)SupposedCauses Supply voltage not as specified Over-voltage detector or DC voltage detection circuit defective PAM control part(s) defective Short circuit inside the fan motor winding.TroubleshootingCorrect the power supply.Replace the outdoor unitPCB.Check for such factors for along term.∗ Try to get restarted acouple of times.(R7150)CautionBe sure to turn off power switch before connect or disconnect connector,or parts damage may be occurred.NOYESYESNOYES(Precaution before turning on the power again)NO Replace fan motor andoutdoor unit PCB.Check the supply voltage.Rotate fan by hand.Disturbance factors∗ Noise ∗ Power supply distortionRepeat acouple of times.Make sure the power has been off forat least 30 seconds.Turn on thepower again. Systemrestarted?Does fan rotatesmoothly?Supply voltage asspecified?
