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Daikin Error Codes – System

Daikin Error Codes – System

Simple Self-Diagnosis by Malfunction Code For Daikin System

For error codes beginning with U, stay on this page and scroll down

For error codes beginning with 6, 7, 8 or 9, find causes here

For error codes beginning with A or C, find causes here

For error codes beginning with E, F, H, J, L, M or P, find causes here

 

System Error Codes and ContentsSupposed causesParts affected
U0
Shortage of refrigerant
Refrigerant shortage and refrigerant clogging (wrong
piping)
Defective thermistor
Defective low pressure sensor
Defective outdoor unit main PCB
RA, SkyAir, VRV, Package, Chiller
U1
Reverse phase, open phase
Power supply reverse phase
T phase open phase
Defective outdoor unit PCB (A1P)
RA, SkyAir, VRV, Package, Heat reclaim ventilator, Chiller, Fan coil
U2
Malfunction of power supply or
instantaneous power failure
Abnormal power supply voltage
Instantaneous power failure
Defective main circuit wiring
RA, SkyAir, VRV, Package, Chiller, Fan coil
U3
Check operation not executed or
transmission error
Check operation is not executed.RA, SkyAir, VRV, Package, Heat reclaim ventilator, Chiller, Fan coil
U4
Malfunction of transmission
between indoor and outdoor unit
Short circuit in indoor-outdoor or outdoor-outdoor
transmission wiring (F1 / F2), or wrong wiring
Outdoor unit power supply is OFF
System address does not match
Defective indoor unit PCB
Defective outdoor unit PCB
RA, SkyAir, VRV, Package, Heat reclaim ventilator, Chiller, Fan coil
U5
Malfunction of transmission
between indoor unit and remote
controller
Transmission error between indoor unit and remote
controller
Connection of 2 main remote controllers (when using 2
remote controllers)
Defective indoor unit PCB
Defective remote controller PCB
Transmission error caused by noise
RA, SkyAir, VRV, Package, Chiller, Fan coil
U6
Malfunction of transmission
between indoor units
Faulty wiring
External factor (Noise etc.)
Defective indoor unit PCB
VRV, Package, Chiller, Fan coil
U7
Malfunction of transmission
between outdoor units or outdoor
storage unit
Connection error of transmission wirings between outdoor
unit and external control adaptor for outdoor unit
Connection error of transmission wirings between outdoor
units
Defective outdoor unit PCB
RA, VRV, Package, Chiller, Fan coil
U8
Malfunction of transmission
between remote controllers
Transmission error between main and sub remote
controller
Connection between sub remote controllers
Defective remote controller PCB
SkyAir, VRV, Package, Heat reclaim ventilator, Chiller, Fan coil
U9
Malfunction of transmission (other
system)
Transmission error between other indoor and outdoor units
Defective electronic expansion valve of other indoor unit
Defective indoor unit PCB of other indoor unit
Improper connection of transmission wiring between
indoor and outdoor unit
SkyAir, VRV, Package, Chiller, Fan coil
UA
Defect of indoor/outdoor power
supply
Wrong model connections
Improper power supply
Wrong PCB connected
Defective PCB
RA
UA
Improper combination of indoor
and outdoor units
Excess of connected indoor units
Defective outdoor unit PCB
Mismatch of the refrigerant type of indoor and outdoor unit
Setting of outdoor unit PCB was not carried out after
replacing to spare PCB
SkyAir, VRV, Package, Chiller
UA
Remote temperature setting wire
disconnection
Remote temperature setting wire disconnection
Defective connector contact
Heat reclaim ventilator
UC
Malfunction of setting of centralized
control equipment address
Address duplication of centralized control equipment
Defective indoor unit PCB
SkyAir, VRV, Package, Heat reclaim ventilator, Chiller, Fan coil
UE
Malfunction of transmission
between indoor unit and
centralized control equipment
Transmission error between optional controllers for
centralized control equipment and indoor unit
Connector for setting main controller is disconnected.(or
disconnection of connector for independent / combined
use changeover switch.)
Defective PCB for central remote controller
Defective indoor unit PCB
SkyAir, VRV, Package, Heat reclaim ventilator, Chiller, Fan coil
UF
System is not set yet
Improper connection of transmission wiring between
indoor-outdoor units and outdoor-outdoor units
Failure to execute check operation
Defective indoor unit PCB
Stop valve is not opened
SkyAir, VRV, Package, Heat reclaim ventilator
UH
Malfunction of system
Improper connection of transmission wiring between
indoor-outdoor units and outdoor-outdoor units
Defective indoor unit PCB
Defective outdoor unit PCB
RA, VRV, Package
UJ
Malfunction of transmission
(accessory device)
Defect of accessory devices
Faulty wiring
RA, SkyAir, VRV, Package, Chiller
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