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Furnace cfm

Hello to all

What is the rule of thumb/how do you calculate how much cfm you need for a furnace. Like we say 400 cfm for each ton of cooling.

Thanks mike.


  • Big Ed_4
    Big Ed_4 Member Posts: 1,754

    200 CFM's per 10K BTU's 80% plus ,150 CFM's per 10K BTU's 90% plus at a 55* rise
    I have enough experience to know , that I dont know it all