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Category 4 Common Vents

Zman Member Posts: 7,573
Working on a project where we are trying to eliminate one big boiler and install 2 smaller ones. The vent is cat 4 and brand new. It runs short vertical then horizontal then vertical again.
The project is being professionally engineered. I am just looking for resources to help me better understand the subject.
"If you can't explain it simply, you don't understand it well enough"
Albert Einstein


  • hot_rod
    hot_rod Member Posts: 22,262
    The vent manufacturers have good engineering data, probably online.
    The National Fuel Gas Handbook is another good resource. The handbook has the codes but also interpretation of them, which helps.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream