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duct ?

The supply house that sells equipment should have these availiable.


  • joe_65
    joe_65 Member Posts: 3
    duct ?

    installing a forced air system. have the heat loss done need the charts for sizeing the duct does anyone know where to find these ?
  • Eugene Silberstein
    Eugene Silberstein Member Posts: 1,380
    You can use...

    You can use the tables in the back of the Manual J book to obtain the diameter of the duct you will need for each area the system serves. From there, you will need to convert from the round size to its equivalent square or rectangular duct size.

    As Mike mentioned you can obtain a "Ductulator" from your local supply house for about $20.

    By the way, in order to properly size the ducts, you will need to determine the friction rate for the specific air distribution system you are installing. Using an incorrect friction rate can result in inadequate system operation.

    Remember to measure twice and saw once.
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