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Apprentice answer

Why does a volume damper leak when it is bolted metal-to-metal into a sleeve

2nd YearSealing, Leakage & MasticStandard Correction

Metal-to-metal damper frames can leak around the perimeter. Back it off, clean the faces, add the approved gasket/seal detail, re-tighten evenly, and retest.

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Plain-English answer

A damper frame bolted into a sleeve without gasket or seal can leak around the entire perimeter even if the fasteners are tight.

Find the leak path, unbolt only as allowed, clean both faces, install the approved gasket/sealant detail continuously around the frame, tighten evenly, and retest under fan pressure.

Ask Foreman

The volume damper frame at [location] is leaking around the sleeve. I checked the perimeter and it appears metal-to-metal. Do you want it backed off and gasketed/sealed per detail?

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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