
Self-diagnosis function
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1. Wiring defect between HR unit and
upgraded 485 modem
2. Defect of the upgraded 485 PCB modem
3. Defect of the HR unit PCB
Error No.
Error type
Error point
Main reasons
4 series upgraded 485 com-
munication error
between HR unit and HR
unit modem
Communication error
between HR unit and
the upgraded 485
modem
205C#HR
1. Defect of power cable of HR unit or com-
munication line connection
2. Error of address allocation rotary switch
setting of HR unit
3. Defect of the HR unit PCB
Error No.
Error type
Error point
Main reasons
When the HR unit address is
set duplicated
at the 4 series upgraded 485
communication
Duplicate address error
of HR unit
206C#HR
n
Error diagnosis and countermeasure flow chart
1) Check the communication connection between HR unit and the upgraded 485 modem, and check for the red
LED on
2) Reset the outdoor unit and the power of HR unit if the red LED of the upgraded 485 modem is on
3) Replace the upgraded 485 modem if the red LED is flashing at the upgraded 485 modem
4) Replace the HR unit PCB if the red LED of the upgraded 485 modem is flashing even after replacing the
upgraded 485 modem.
n
Error diagnosis and countermeasure flow chart
1) Check whether the rotary switch setting of HR unit PCB is set differently for HR units
2) Reset the outdoor unit and the power of HR unit by setting the rotary switch of HR unit PCB differently for HR
units
3) Perform the auto addressing again after performing the number 2 process
4) Replace the corresponding HR unit PCB if the same error code is occurred even after performing the number 3
process
• The above error code is only occurred at the upgraded 485 communication (9600bps communication)
• Refer to the installation manual of the outdoor unit for the address setting to HR unit rotary switch for HR units