Specifications
Table Of Contents
- Cover
- Table of Contents
- Part 1 List of Functions
- Part 2 Specifications
- Part 3 Printed Circuit Board Connector Wiring Diagram
- Part 4 Function and Control
- Part 5 Operation Manual
- Part 6 Service Diagnosis
- 1. Caution for Diagnosis
- 2. Problem Symptoms and Measures
- 3. Service Check Function
- 4. Code Indication on the Remote Controller
- 5. Troubleshooting
- 5.1 Indoor Units
- 5.2 Outdoor Units
- 5.3 Indoor Unit PCB Abnormality A1
- 5.4 Freeze-up Protection Control or High Pressure Control A5
- 5.5 Fan Motor or Related Abnormality A6
- 5.6 Thermistor or Related Abnormality (Indoor Unit) C4,C9
- 5.7 Front Panel Open / Close Fault C7
- 5.8 Signal Transmission Error (between Indoor and OutdoorUnit) U4
- 5.9 Unspecified Voltage (between Indoor and Outdoor Units) UA
- 5.10 Freeze-up Protection Control A5
- 5.11 Outdoor Unit PCB Abnormality E1
- 5.12 OL Activation (Compressor Overload) E5
- 5.13 Compressor Lock E6
- 5.14 DC Fan Lock E7
- 5.15 Input Over Current Detection E8
- 5.16 Discharge Pipe Temperature Control F3
- 5.17 High Pressure Control in Cooling F6
- 5.18 Compressor Sensor System Abnormality H0
- 5.19 Position Sensor Abnormality H6
- 5.20 CT or Related Abnormality H8
- 5.21 Thermistor or Related Abnormality (Outdoor Unit) P4,J3,J6,J8,J9,H9
- 5.22 Electrical Box Temperature Rise L3
- 5.23 Radiation Fin Temperature Rise L4
- 5.24 Output Over Current Detection L5
- 5.25 Insufficient Gas U0
- 5.26 Low-voltage Detection or Over-voltage Detection U2
- 5.27 Signal Transmission Error (on Outdoor Unit PCB) U7
- 5.28 Anti-icing Function in Other Rooms / UnspecifiedVoltage (between Indoor and Outdoor Units) UA,UH
- 6. Check
- Part 7 Removal Procedure
- Part 8 Others
- Part 9 Appendix
- Index
- Drawings & Flow Charts
Troubleshooting SiBE12-713
244 Service Diagnosis
5.8 Signal Transmission Error (between Indoor and Outdoor
Unit)
Remote
Controller
Display
U4
Method of
Malfunction
Detection
The data received from the outdoor unit in indoor unit-outdoor unit signal transmission is
checked whether it is normal.
Malfunction
Decision
Conditions
When the data sent from the outdoor unit cannot be received normally, or when the content of
the data is abnormal.
Supposed
Causes
Faulty outdoor unit PCB.
Faulty indoor unit PCB.
Indoor unit-outdoor unit signal transmission error due to wiring error.
Indoor unit-outdoor unit signal transmission error due to disturbed power supply waveform.
Indoor unit-outdoor unit signal transmission error due to breaking of wire in the connection
wires between the indoor and outdoor units (wire No. 2).
Short circuit inside the fan motor winding.