Then finish up by sealing the access hatch with self sticking foam weatherstrip photos 10 and 11.
How to seal air handler plenum in attic.
Leaks in hvac air handlers can usually be seen felt and heard.
Your plenum will typically be located in an unheated area of the house such as the attic or garage.
My mother has had me going up into her attic to seal the leaky ducts and parts of the plenum air handler that join up to the furnace and coil units.
This is a common occurrence in florida garages.
Hot humid air mixes with the cold internal air of the air handler by the cold metal of the unit causing condensation.
Common places to find them are at ill fitting cover panels or those with missing screws.
And plenum and return air connectors.
Where air conditioning pipes enter the housing grommets may be missing or leaky.
Humid air and air flow.
If your hatch rests directly on the moldings like ours did add 2 1 2 in wide stops around the.
If an air handler is in a garage attic crawlspace or closet it might experience less air flow and humid air.
Anyhow the return box and the other box that has the ducts coming out of it are made of sheet metal.