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Co ppm limit for combustion tes

What is the max co ppm limit up the flue and we're is it documented. I always go for 0 to 150 ppm in both residential and commercial but looking for a documented code limit.


  • Ironman
    Ironman Member Posts: 7,379
    400 ppm as per the EPA, but I wouldn't want to go that high. There's also ambient maximum levels/hours exposure. You'll have to google it, but it is on their site.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Tim McElwain
    Tim McElwain Member Posts: 4,628
    The ANSI Standard is 400 PPM allowable in a flue sample. We however strive to get 100 PPM or less. A lot of new Mod/Cons give a number they want for their equipment. Contact me at gastc@cox.net and I will share some information with you.