Specifications
Table Of Contents
- Cover
- Table of Contents
- Part 1 General Information
- Part 2 Specifications
- Part 3 Refrigerant Circuit
- Part 4 Function
- Part 5 Test Operation
- Part 6 Troubleshooting
- Part 7 Appendix
- 1. Piping Diagrams
- 2. Wiring Diagrams for Reference
- 3. List of Electrical and Functional Parts
- 4. Option List
- 5. Piping Installation Point
- 6. Example of connection (R-410A Type)
- 7. Thermistor Resistance / Temperature Characteristics
- 8. Pressure Sensor
- 9. Method of Checking the Inverter’s Power Transistors and Diode Modules
- Part 8 Precautions for New Refrigerant (R-410A)
- Index
- Drawings & Flow Charts
Troubleshooting by Indication on the Remote Controller Si34-704
282 Troubleshooting
3.50
“
U9
”
Indoor Unit: Malfunction of Transmission between
Indoor and Outdoor Units in the Same System
Remote
Controller
Display
U9
Applicable
Models
All models of indoor units
RXQ5P~54P
Method of
Malfunction
Detection
Detect malfunction signal for the other indoor units within the circuit by outdoor unit PCB.
Malfunction
Decision
Conditions
When the malfunction decision is made on any other indoor unit within the system concerned.
Supposed
Causes
Malfunction of transmission within or outside of other system
Malfunction of electronic expansion valve in indoor unit of other system
Defect of PC board of indoor unit in other system
Improper connection of transmission wiring between indoor and outdoor unit
Troubleshooting
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
The outdoor unit PC board
indicated by the malfunction code
U9 is normal.
Check for the indoor unit of other
system, and then conduct
troubleshooting by diagnosis
according to the Malfunction
Code Flowchart.
Re-diagnose by display after
passage of 2 minutes or more.
Continue operation.
NO
"U9"
has been displayed for 2
minutes or more.
NO
All the units are
indicating “U9”.
Turn on all indoor units.
YES
YES