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Apprentice answer

Why did the round volume damper blade get stuck in spiral duct

3rd YearRound, Spiral & Flat Oval DuctCheck first

A damper shaft needs solid support. Reinforce the axle area or replace the damaged fitting before relying on the damper.

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Plain-English answer

A heavy damper blade in high-velocity air can twist thin spiral skin around the axle holes. Once the wall warps, the blade can jam open or shut.

Inspect the damper, patch/replace damaged metal, and use an approved backing plate, bearing block, or factory damper fitting so the shaft stays square.

Ask Foreman

The round damper at [location] is jamming because the shaft is warping the spiral wall. I checked blade movement. Do you want a reinforced damper fitting/backing plate installed?

Verify before acting

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

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