Condensation In Attic Ductwork In Winter

Condensation problem in the ductwork in wintertime question i have a dedicated ductwork system with the air handler in unconditioned attic.

Condensation in attic ductwork in winter.

When the warm air rising from the first floor gets into the duct inlets a lot of condensation forms. Another condensation problem occurs in cold climates in the winter with ac ducts in the attic and a different heating system. The house air with its moisture rises into the ducts cools and condenses the moisture cool air sinks and is replaced with more warm moist air from inside the house. No the radiant barrier will not solve the condensation issue.

Even though the ducts are insulated and my attic is over insulated the air and surfaces inside the ducts will get very cold if the hvac is left off. Think about it condensation on ductwork probably isn t a big problem in phoenix arizona but why. When outside temperatures drop down below about 40 pretty much nov thru march condensation starts forming in the ducts and drips from some of the ceiling registers. If the attic is foam sealed with no leakage to the outside that would work.

Without seeing your duct attic situation one can only speculate but ducts touching each other lying on or in insulation in our climate. Because the average humidity level is 10 20 in phoenix. But i notcied that the condensation only formed when the outside temps fell below about 20 degrees. However an attic in pensacola florida is likely to have a humidity level closer to 100 and the risk of condensation on ductwork would then go up quite a bit.