Service Manual

SiUS041638E
Service Diagnosis 50
Part 6
Service Diagnosis
1. General Problem Symptoms and Check Items .........................................52
2. Troubleshooting with LED .........................................................................53
2.1 Indoor Unit.................................................................................................. 53
2.2 Outdoor Unit ............................................................................................... 53
3. Service Diagnosis .....................................................................................54
4. Troubleshooting ........................................................................................57
4.1 Error Codes and Description ...................................................................... 57
4.2 Indoor Unit PCB Abnormality ..................................................................... 58
4.3 Freeze-up Protection Control/Heating Peak-cut Control ............................ 60
4.4 Indoor Fan Motor (DC Motor) or Related Abnormality ............................... 61
4.5 Thermistor or Related Abnormality (Indoor Unit)........................................ 63
4.6 Low-voltage Detection or Over-voltage Detection...................................... 64
4.7 Signal Transmission Error (between Indoor Unit and Outdoor Unit) .......... 66
4.8 Signal Transmission Error on Outdoor Unit PCB ....................................... 68
4.9 Mismatching of Indoor Unit and Outdoor Unit ............................................ 69
4.10 Outdoor Unit PCB Abnormality................................................................... 70
4.11 OL Activation (Compressor Overload) ....................................................... 71
4.12 Compressor Lock ....................................................................................... 73
4.13 DC Fan Lock (Outdoor Fan)....................................................................... 74
4.14 Input Overcurrent Detection ....................................................................... 75
4.15 Four Way Valve Abnormality...................................................................... 76
4.16 Discharge Pipe Temperature Control......................................................... 78
4.17 High Pressure Control in Cooling ............................................................... 79
4.18 System Shutdown due to Compressor Internal Temperature
Abnormality ................................................................................................ 80
4.19 Compressor System Sensor Abnormality .................................................. 81
4.20 Position Sensor Abnormality ...................................................................... 82
4.21 CT or Related Abnormality ......................................................................... 84
4.22 Thermistor or Related Abnormality (Outdoor Unit)..................................... 86
4.23 Electrical Box Temperature Rise................................................................ 88
4.24 Radiation Fin Temperature Rise ................................................................ 89
4.25 Output Overcurrent Detection .................................................................... 90
5. Check ........................................................................................................92
5.1 Thermistor Resistance Check .................................................................... 92
5.2 Indoor Fan Motor Connector Output Check ............................................... 93
5.3 Power Supply Waveforms Check............................................................... 93
5.4 Electronic Expansion Valve Check............................................................. 94
5.5 Four Way Valve Performance Check ......................................................... 95
5.6 Inverter Unit Refrigerant System Check..................................................... 95
5.7 Inverter Analyzer Check ............................................................................. 96
5.8 Rotation Pulse Check on the Outdoor Unit PCB ........................................ 98