Equivalent Length of Fittings
Total equivalent feet from fitting type and diameter counts.
Example
You enter
- Items type elbow_90_long, diameter 1, count 4; type tee_branch, diameter 1, count 1
You get
- Total equivalent length 12.8 ft
Details, formula, and sources
Sum of per-fitting equivalent lengths from public engineering tables; total run = straight pipe + Σ(equivalent lengths).
ASHRAE Handbook (Fundamentals) by name; engineering-practice consensus values.
ASHRAE Handbook licensed; equivalent-length tables free in published engineering texts.
Estimate. AHJ and licensed mechanical contractor govern. ACCA Manual J / D / S supersede rules of thumb.
Field names used by the API: items, total_equivalent_ft
- Fitting library data/hvac/equivalent-lengths.jsonpublic engineering reference