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Apprentice Q&A · #095

What's the best way to modify a square-to-round transition if the VAV is off-center?

2nd YearField ModsYELLOW · Check First

If the layout has shifted, you can field-modify the transition by trimming back the length of the flat rectangular sheet metal wrapper sides on one axis. * This skews the round collar center point over toward the path of the new VAV alignment line. If the shift is massive, stop and have the shop burn a new asymmetric fitting on the plasma table to avoid choking down the air stream.

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Plain-English answer

If the layout has shifted, you can field-modify the transition by trimming back the length of the flat rectangular sheet metal wrapper sides on one axis. * This skews the round collar center point over toward the path of the new VAV alignment line. If the shift is massive, stop and have the shop burn a new asymmetric fitting on the plasma table to avoid choking down the air stream.

Field checklist

Ask Foreman

Hey boss, I’m checking field mods: What's the best way to modify a square-to-round transition if the VAV is off-center? I found the likely issue and want to verify the next step before I lock it in. Do you want me to adjust it now or check the drawing/detail first?

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Verify before acting

Use this as training guidance. The foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements always control the final answer.

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