Static field route #438

What do I do when offset built too tight causing pressure drop?

Airflow/TAB Impacts From InstallationV136 field-polished — distinct TAB/airflow answer

A tight offset may fit in the ceiling but still hurt performance. Check offset angle, length, and the O.W.L. before fabricating or installing.

Open in Field Rescue Open category

Field checklist

Measure obstruction, offset, and available length.
Use O.W.L.: Offset × fitting multiplier = Length needed.
Check whether the offset creates a hard turn right before a branch, VAV, or diffuser.
Compare against the approved routing/detail.
Ask before forcing a tight offset into a short space.

Ask foreman

This offset is [offset] over [available length]. Does this layout give us enough length, or do you want a different route/fitting?

Do not

Do not build a short aggressive offset just because it clears the obstruction.

Why it matters

A tight offset can solve clearance while creating pressure loss and noise. O.W.L. keeps the layout honest before cutting metal.

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