U4 Or Uf Transmission Error (Between Indoor Unit And Outdoor Unit) - Daikin R71FUV1 Service Manual

Troubleshooting by Remote Controller
U4
3.92
(Between Indoor Unit and
Outdoor Unit)
Remote Controller Display
U4 UF
or
Applicable Models
R(Y)-FU
Method of Error Detection
Micro-computer checks if transmission between indoor
and outdoor units is normal.
Error Decision Conditions
When transmission is not carried out normally for a
certain amount of time
Supposed Causes
Wiring indoor-outdoor transmission wire is incorrect.
Defective indoor unit PCB
Defective outdoor unit PCB
External factor (Noise, etc.)
UF
or Transmission Error
Si20-701_B
375