I have learned of a popular tactic from many of my customers. Apparently I have competitors in the Air Duct Cleaning business who quote people a price to clean ducts only in order to get their foot in the door. Once in the customers home, they up-sell them on cleaning trunk lines and furnace. Besides being a distasteful tactic, it is also not a logical approach to proper air duct cleaning.
Using our method, if we were to only clean the air ducts, we would have dislodged lots of dust and debris and dropped it into the trunk line. I'm not even sure if the debris would be able to be removed from the trunk line without actually cleaning the trunk lines. We have cleaned up the mess left by these comanies several times. Customers call and explain that excessive amounts of dust are coming out of their vents, and yet they just had them cleaned. Most often the problem is that the ducts were cleaned without cleaning the entire system. This is both a waste of the customers money and the air duct cleaner's time.
My recommendation is to clean the entire system and settle for nothing less. You must remove all dirt, dust and debris from the entire system in order to experience the full benefit of air duct cleaning. Otherwise, it seems to me you are just moving the dirt around.
When getting a quote for air duct cleaning - be sure to ask if the price includes cleaning the furnace (blower, condenser coils, etc), cleaning the trunk lines or mains, as well as the air ducts. Even though you'll spend more money, you'll be glad you did once you see the tremendous results of a thorough, professional air duct cleaning job.