Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.

If you've found help here, check back in to let us know how everything worked out.
It's a great way to thank those who helped you.
Need to contact us? Visit


JHKJHK Member Posts: 10
As a rule of thumb how many cfm is required per 1,000 btu's output for a gas furnace?


  • Empire_2Empire_2 Member Posts: 2,343
    Funny Q:? in that:

    Are you talking Forced air, boiler, what do you want your delta T to be?, Application etc...  A/C sometimes ratted at 400cfm/ton, but not always due to conditions that have to be met.  I have seen cooling specs. for 325cfm/ton.  If your Q? for cfm also must have the size of duct, it's current profected static pressure etc..

      I guess I would like to know what you are trying to do???

    Mike T.
  • J HeritageJ Heritage Member Posts: 27
    Depends upon efficiency

    80% is abour 130 cfm per 10,000 btu

    90% is about 150 cfm per 10,00 btu

    This is for heating airflow
This discussion has been closed.


It looks like you're new here. If you want to get involved, click one of these buttons!