Duct Leakage

A couple photos of problem duct work and thermal images of air leakage in a customers home. The service call was to identify the cause of moisture in the wall below a supply duct. I found that the 6″ duct supply to the foyer had wet duct wrap insulation and this moisture was dripping into an interior wall. The duct wrap insulation was installed so tightly that it lost the R value and the warm moist attic air was condensing on the round duct pipe. Water was coming from where the duct pipe was pressing against the wood top plate of the wall and flowing into the sheet rock wall. The fix was to move the duct off of the wood top plate, remove the wet insulation, seal duct leakage with mastic and spray foam, and insulate the pipe with duct wrap. Now the duct will not sweat and ruin sheet rock.

This thermal picture shows the cold air leaking behind the tape and insulation that hid this ugly looking duct tap. When I peeled of the surface tape and exposed the metal pipe the duct leakage is evident, poor craftsmanship in duct work.  There are about 18 supply ducts in this home….imagine the total duct leakage.

Poorly cut supply tap in round pipe hidden behind insulation and tape

Sealed air gaps with spray foam and gray duct mastic to seal joints

Sealed, insulated and taped duct

This thermal picture is of a ceiling supply grill taken during air conditioning usage which shows the hot bright red infiltration behind and around the duct boot, sheet rock and supply grill. The hot attic air is leaking around the sheet rock cut out for the duct boot tabs and the supply grill. We can stop this infiltration by removing the supply grill and using caulk and spray foam to seal air gaps.

Ceiling supply grill

Call Air Max Heating & Cooling LLC at 601-939-0015 or visit us at www.airmax.ms to discuss your leaking duct work or schedule a duct work diagnostic service call.

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