After the Air Duct Cleaning, What's Next?

As part of a residential duct cleaning, the professional air duct cleaning company may recommend the application of chemicals that will perform air duct sanitizing and air duct coating repair functions.

1)  A Sealant

If you choose to have it done, sealant will be applied by an air duct company throughout the HVAC system.  The hope is that using the sealant will help prevent particles from the air duct escaping into your home.  According to the EPA, no hard evidence exists as to whether these chemicals, as claimed by the manufacturers, provides the indoor air quality homeowners what they expect them to.  Some laboratory tests have shown that when sprayed into a ventilation system, the sealant chemical does not coat the entire duct surface.  Three of the professional organizations most concerned with air quality, National Air Duct Cleaners Association (NADCA), the North American Insulation Manufacturers Association (NAIMA) and the Sheet Metal and Air Conditioning Contractors’ National Association (SMACNA) don’t recommend that sealants be applied in every instance.  There are, however, some situations where a sealant is helpful, such as if fiber glass connected with the duct system needs to be repaired of when fire damage is being repaired. 

2) A Biocide

A biocide is a chemical that sanitizes the duct system, killing mold, fungi, bacteria and other germs, and preventing their future growth.  Most biocides have only been shown to be effective on ducts comprised not of fiber glass, but of plain, unadorned sheet metal.  Like any other chemical product designed to kill something, there are risks in allowing the biocide to be applied, including the risk of an allergic reaction to the chemical by a member of your family.  Because of this, if your air duct cleaning service recommends the application of a biocide into your duct system, ask the service to provide visible proof of the growths in your duct work.  Also ask if the service can help you plan how to prevent growth in the future by controlling the condition that led to the mold (usually excessive moisture in some fashion) instead of using the biocide.  Bear in mind that only a professional such as Air Duct Cleaning Hacienda Heights can correctly identify if, and what types of, microbes are growing in your system.