Transmission Error Between Indoor And Outdoor Units In The Same System - Daikin SkyAir RZR-TA Series Service Manual

SiUS281811E
4.53 Transmission Error between Indoor and Outdoor Units in
the Same System
U9
Error Code
Applicable
All indoor units
All outdoor units
Models
Method of Error
Error signal for the other indoor units is detected within the system by outdoor unit PCB.
Detection
Error Decision
The error decision is made on any other indoor unit within the system concerned.
Conditions
Supposed  Transmission error within or outside of other system
Causes  Defective electronic expansion valve in indoor unit of other system
 Defective PCB of indoor unit in other system
 Improper connection of transmission wiring between indoor and outdoor unit
Troubleshooting
Part 6 Service Diagnosis
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Turn ON all indoor units.
NO
All the units are
indicating U9.
YES
U9 has been
NO
displayed for 2 minutes
or more.
YES
Troubleshooting by Error Codes
Continue the operation.
Re-diagnose by display after
passage of 2 minutes or more.
The indoor unit PCB indicated by
the error code U9 is normal.
Check for the indoor unit of other
system, and then conduct
troubleshooting by diagnosis
according to the Error Code
Flowchart.
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