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How do I size a boiler stack?

Laura_2 Member Posts: 1
I am replacing a gas fired atmospheric boiler with a newer, more efficient boiler with forced draft. I want to make sure that the existing stack is correctly sized for my new boiler. How do I calculate the correct stack diameter and height?


  • The gas code

    The NFPA 54 Gas Code has a guide in it, but the manufacturer of the boiler will have published minimums and maximums, and they can be MORE restrictive than the code.

    It should be in your boiler instruction manual.

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