Technical directory · Ducts
Duct liner and moisture
Porous or internally insulated duct material cannot always be cleaned effectively when wet or contaminated.
What to observe
Document the material and moisture source with photographs before disturbing it.
A field example
A wet insulated return deserves a search for condensation or a leak. A surface spray can leave moisture behind the facing, so damaged porous material may require replacement after the source is corrected.
What the written work should say
Fix water intrusion and get an appropriate assessment of affected material; replacement can be more suitable than surface cleaning.
Where this task stops
A spray or fragrance does not repair wet liner or eliminate the underlying water source.