Hydronic Baseboard Output

BTU/hr from manufacturer-attributed BTU/ft tables interpolated by water temp.

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Details, formula, and sources

Hydronic baseboard BTU/ft from manufacturer tables interpolated by water temperature; flow correction applied per manufacturer curve.

Slant/Fin Fine Line 30 typical-curve and high-output reference (manufacturer-attributed).

Free at slantfin.com.

Estimate. AHJ and licensed mechanical contractor govern. ACCA Manual J / D / S supersede rules of thumb.

Field names used by the API: water_temp_F, flow_gpm, length_ft, model, btu_per_ft, btu_total

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