21Oct air ducts air conditioning service Houston, air duct cleaning, air duct cleaning service, Air Duct Replacement Houston, air ducts, Chicago furnace cleaning, commercial air duct cleaning How Much Does Duct Replacement Cost? The average cost to replace HVAC ductwork is around $285 per duct run, and it is determined by the number of HVAC duct runs to be replaced, the length of each run, the type and size of the replacement ductwork,...