In the rooms of your house, on the walls and floor, you will find sheet metal grilles, which cover the openings of the supply and return ducts. The supply grilles, often called diffusers, are designed so that the quantity of air passing through them can be adjusted from completely open to completely shut. Usually every room has a supply opening, including bathrooms and walk-in closets. The quantity of return openings is usually less than the supply and it is quite common to see buildings designed so that several rooms or areas of the house share a common return opening, such as the case where there will be one return in a hallway servicing two or three bedrooms. In many older and newer homes however, it is not unusual to find a return opening in every room with the exception of bathrooms, kitchens, and laundry rooms.

The only way to remove this collection of un-savory material is to physically extract, by one means or another, the dust that has accumulated in your air duct system. Hence the name 'Air Duct Cleaning'.

Your air ducts can be cleaned in one of two ways.
The first is to run agitation and vacuums into the ducts through the openings in the room. As the equipment works its way down the run, the dust is agitated by a brush and the loosened dust is vacuumed out. As the brushes used in this method are round, this system is ineffective on rectangular or square ductwork in capturing the dust that adheres to the inside corners. As a result, many operators using this equipment have to apply a glue-like sealant throughout the system to literally glue what dust they could not get out against the walls of the ducts. Over time this sealant degrades and becomes part of the contamination you need to remove.

Note: There are times, such as after fires or in the case of heavy smoke ( even cigarette smoke) where a sealant is required to contain the odor. You, the consumer, should be wary of companies who use sealants as general operating procedure, as this is a fairly good indicator that they are either using substandard equipment or they intend to glue down your dust as opposed to removing it.

The second method, utilizing negative pressure, is superior to the one previously mentioned in practically every application. Simply stated, this is a push-pull system with a large vacuum attached to the large ducts near the furnace drawing the dust toward it, while at the same time high pressure air is introduced into the openings, pushing the dust toward the vacuum.

By incorporating this method, the otherwise inaccessible areas of your duct system are reached. The specialized nozzles through which the high pressure air passes blast the dust from all surfaces of the duct, regardless of their shape.

Note: other mechanical devices such as fixed and rotating brushes are often used in conjunction with the high pressure air to help agitate and loosen the dust from the walls of the duct.
As the dust gets blasted off the interior surface, it gets caught up in the air stream created by the large vacuum and drawn into it where it is collected in specialized bags. These vacuums are either truck-mounted or portable and either is acceptable as long as they are drawing the air in the ducts at the volume needed to keep the dust particle airborne.

For more information and a free in-home inspection and quote, give us a call. We'll be glad to answer any questions you may have regarding air duct cleaning.

If you are thinking of installing any of our mentioned air quality products, please give us a call.
We will be happy to answer your questions!