Back to Training HVAC 101 0% Complete 0/0 Steps Dampers Explained Insulation Check Finding Signs Of Rats In The Attic Space Drawing A System Duct Inspection Heating Sequence Of Operation - Standard Furnace Ladders, Drops & Attic Access 5 Inch Media Filter Replacement Remove Locking Refrigerant Caps HVAC 101 Duct Inspection Video 5 of 9 In Progress ← Previous Next→ Duct Inspection Mike goes over where to start and what to look for on a duct inspection in an attic.