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Buderus GB boiler, 9U error code, solid red light on UBA any help?

tim smith
tim smith Member Posts: 2,738
Wont come out of 9u error, even tried new UBA still wont come out. Checked and cleaned all molex/polarized plug connections. Rrrrrr, frustrating. Was too late yesterday afternoon to get a hold of tech support. Any input appreciated guys.


  • Docfletcher
    Docfletcher Member Posts: 487
    edited April 2016
    Went online and found fault code 9U is defective KIM. Service manual link. Map for 9U page 41.

    Wiring to gas-valve assembly incorrect,
    or loose wiring connections in UBA. See if the map can help.

  • Docfletcher
    Docfletcher Member Posts: 487
    Sorry Tim I did not see the 2nd posting. I see your already are on the map.
  • tim smith
    tim smith Member Posts: 2,738
    thanks guys for your help, ended up even though UBA was seated all the way in sub base, some times the KIM card does not seat all the way in UBA due to it pushes too far back into the sub base holder. They say pull kim card out of sub base and insert into UBA before mounting UBA to base. Go figure? Local tech rep for Buderus had not heard of that?