Ashrae: Duct Fitting Database Excel

=XLOOKUP([@Fitting_Ref], ASHRAE_DB[A:Fitting_Code], ASHRAE_DB[Loss_Coefficient]) If you have variable geometry (e.g., a transition where W1/W2 changes), use XLOOKUP with approximate match to find the closest geometric parameter. With coefficient C , velocity pressure Pv (in inches w.g. or Pa), the loss is:

In Duct_Calc , cell C2 (where you need the loss coefficient): ashrae duct fitting database excel

In Excel: = [@Coefficient] * (0.602 * ([@Velocity_FPM]/4005)^2) for IP units. Use SUMIFS to total all losses for each air handler. This yields your fan selection point instantly. Advanced Tips: Beyond Basic Lookup Once you have the ASHRAE Duct Fitting Database Excel file, you can build advanced features: 1. Automated Interpolation Between Table Values Many fittings lack exact matches for your dimensions. Use FORECAST.LINEAR : a transition where W1/W2 changes)