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Apprentice answer

Why is a sloped spiral run sliding downhill in teardrop hangers

3rd YearRound, Spiral & Flat Oval DuctStop and get direction

A sloped round run needs a positive anchor point. Loose loop hangers can cradle the pipe but may not stop downhill drift.

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Plain-English answer

When a round duct run slopes for a long distance, its dead weight has a downhill component. Teardrop or loop hangers may let the pipe walk down the slope, especially with fan vibration.

Install an approved fixed support or saddle anchor at the proper location so the duct cannot slide into equipment, fittings, or terminal boxes. Check the load path and get direction if the run is heavy or high overhead.

Ask Foreman

The sloped spiral run at [location] is sliding downhill in loop hangers and loading the equipment connection. I think it needs a fixed saddle/trapeze anchor. Do you want it held and rebuilt?

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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