Panasonic CU-4E24RBU Service Manual

Also see for CU-3E19RBU: Operating instructions Service manual Service manual Service manual Installation manual

54DiagnosisdisplayAbnormalityorprotectioncontrolLED 6 LED 5 LED 4 LED 3 LED 2 LED 1 AbnormalityjudgmentProtectionoperation Problem Check locationH99Indooroperating unitfreezeprotectionO O O - - Indoor freezeprotection (Cooling) Check indoorheat exchanger Air filter dirty Air circulationshort circuitF114-way valveswitchingabnormalityO O O O4 timeshappen within30 minutes- 4-way valve switchingabnormal 4-way valve Lead wire andconnectorF17Indoor standbyunits freezingabnormalityO3 timeshappen within40 minutes-Wrong wiring andconnecting pipe,expansion valveleakage Checkindoor/outdoorconnection wireand pipe Indoor heatexchanger sensorlead wire andconnector Expansion valvelead wire andconnectorF90Power factorcorrection(PFC) circuitprotectionO O4 timeshappen within20 minutes- Power factor correctioncircuit abnormal Outdoor PCBfaultyF91RefrigerationcycleabnormalityO O4 timeshappen within60 minutes- Refrigeration cycleabnormal Insufficientrefrigerant orvalve closeF93CompressorabnormalrevolutionO O O4 timeshappen within20 minutes- Compressor abnormalrevolution Power transistormodule faulty orcompressor lockF94CompressordischargepressureovershootprotectionO O4 timeshappen within30 minutes- Compressor dischargepressure overshoot CheckrefrigerationsystemF95Outdoorcooling highpressureprotectionO O O4 timeshappen within20 minutes- Cooling high pressureprotection Checkrefrigerationsystem Outdoor air circuitF96PowertransistormoduleoverheatingprotectionO O O4 timeshappen within30 minutes- Power transistormodule overheat PCB faulty Outdoor air circuit(fan motor)F97CompressoroverheatingprotectionO O O O3 timeshappen within30 minutes- Compressor overheat  InsufficientrefrigerantF98Total runningcurrentprotectionO O3 timeshappen within20 minutes- Total current protection Checkrefrigerationsystem Power source orcompressor lockF99Outdoor directcurrent (DC)peak detectionO O OContinuoushappen for7 times-Power transistormodule currentprotection Power transistormodule faulty orcompressor lockLED 1 illuminate is indicated that outdoor unit is operating normally. If the LED 1 is switched off or flashing, check thepower supply and self-diagnosis indication.● - - - - - - Illuminate○ - - - - - - FlashingBlank - - - - - - OFF