Static field route #15109

Duct is sweating or condensation is showing after startup. What do I check?

Insulation, Vapor Barrier & Condensation Controlyellow

Treat sweating duct as an insulation/vapor-barrier and operating-condition problem. Look for missing insulation, open seams, crushed wrap, torn vapor barrier, exposed cold metal, bad joints, or unusual humidity/temperature conditions.

Open in Field Rescue Open category

Field checklist

Duct system type
Where moisture starts and stops
Insulation/vapor barrier continuity
Hanger/saddle/penetration damage
Room humidity or special environment

Ask foreman

This duct is sweating at [location/system]. I checked insulation continuity and vapor barrier damage. Do you want me to repair wrap, check operating conditions, or hold for startup/TAB direction?

Do not

Do not cover wet insulation, ignore mold/ceiling damage risk, or patch vapor barrier without verifying the cause.

Why it matters

Condensation can damage ceilings, insulation, finishes, and indoor air quality. The fix depends on insulation, vapor barrier, humidity, and system operation.

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