Air Duct Cleaners

Truck-mounted or portable air duct cleaning?

Autumn asked: Which is really the best method? What gets the ducts cleanest? Also, some companies now offer the installation (for about $400) of in-line UV light (which kills mold, bacteria). Does anyone have one of these units? Does it help you? Note: Change the 3M disposable furnace filter every 3 months, & ductwork is [...]