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  1. #1
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    Duct heat gain formula



    Which formula should i use to measure the capacity of a ducted unit running in heating.

    I can measure the air quantity and the temp on the return air grill and then the temp of the supply air.
    In metric please!



  2. #2
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    Re: Duct heat gain formula

    Would the following be correct:

    Kw = l/s (air velocity) x kj/kg K (SHC air) x kg/l (air density in liters) x (air temp on coil - air temp off coil)

    Therefore

    Kw = l/s x SHC x air density x temp diff

    or

    Kw = cubic mters air/hour x SHC x air density in cubic meters x temp diff .all divided by 3600.

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