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Noritz CB-199 NG; Error Code 11

padosi Member Posts: 8
edited May 2022 in Gas Heating
The above unit is not able to maintain a fire and I am getting the Error Code 11. I opened the fire detector window (pic) attached and there seems to be some cracks that have developed. I have ordered a window replacement kit from Noritz and it might include a sealant along with new gaskets.
If so, is it safe to use this unit or will I have to replace the entire heat exchange unit?
Would greatly appreciate any input.

Thank you in advance!


  • Lost_aussie
    Lost_aussie Member Posts: 10
    Hi Padosi,

    I have exactly the same issue with the corroded/damaged gasket, opaque sight glass and the flame detector failing to detect the flame. It's temporarily 'fixed' with the spare gasket (That shipped with the unit) and a wiped clean and 'less opaque' sight glass. There is a small crack on the bottom, similar to your photo.

    What did you end up finding out on your heater? Hopefully you have it all rectified. Did you have Noritz replace the heat exchanger under warranty?