Commercial and Residential air duct cleaning madison

 EPA websit:

Most people are now aware that indoor air pollution is an issue of growing concern and increased visibility. Many companies are marketing products and services intended to improve the quality of your indoor air. You have probably seen an advertisement, received a coupon in the mail, or been approached directly by a company offering to clean your air ducts as a means of improving your home's indoor air quality. These services typically — but not always — range in cost from $450 to $1,000 per heating and cooling system, depending on:
the services offered

• the size of the system to be cleaned
• system accessibility
• climatic region
• level of contamination

If you decide to have your heating and cooling system cleaned, it important to make sure the service provider agrees to clean all components of the system and is qualified to do so.

Duct cleaning generally refers to the cleaning of various heating and cooling system components of forced air systems, including the supply and return air ducts and registers, grilles and diffusers, heat exchangers heating and cooling coils, condensate drain pans (drip pans), fan motor and fan housing, and the air handling unit housing (See diagram).

If not properly installed, maintained and operated, these components may become contaminated with particles of dust, pollen or other debris. If moisture is present, the potential for microbiological growth (e.g., mold) is increased and spores from such growth may be released into the home's living space. Some of these contaminants may cause allergic reactions or other symptoms in people if they are exposed to them. If you decide to have your heating and cooling system cleaned, it is important to make sure the service provider agrees to clean all components of the system and is qualified to do so. Failure to clean a component of a contaminated system can result in re-contamination of the entire system, thus negating any potential benefits. Methods of duct cleaning vary, although standards have been established by industry associations concerned with air duct cleaning. Typically, a service provider will use specialized tools to dislodge dirt and other debris in ducts, then vacuum them out with a high-powered vacuum cleaner.

In addition, the service provider may propose applying chemical biocides, designed to kill microbiological contaminants, to the inside of the duct work and to other system components. Some service providers may also suggest applying chemical treatments (sealants or other encapsulants) to encapsulate or cover the inside surfaces of the air ducts and equipment housings because they believe it will control mold growth or prevent the release of dirt particles or fibers from ducts. These practices have yet to be fully researched and you should be fully informed before deciding to permit the use of biocides or chemical treatments in your air ducts. They should only be applied, if at all, after the system has been properly cleaned of all visible dust or debris.

Note: Use of sealants to encapsulate the inside surfaces of ducts is a different practice than sealing duct air leaks. Sealing duct air leaks can help save energy on heating and cooling bills. For more information, see EPA's Energy Star website.

If you choose to have your ducts cleaned, the service provider should:

Open access ports or doors to allow the entire system to be cleaned and inspected.

Inspect the system before cleaning to be sure that there are no asbestos-containing materials (e.g., insulation, register boots, etc.) in the heating and cooling system. Asbestos-containing materials require specialized procedures and should not be disturbed or removed except by specially trained and equipped contractors.

Use vacuum equipment that exhausts particles outside of the home or use only high-efficiency particle air (HEPA) vacuuming equipment if the vacuum exhausts inside the home.

Protect carpet and household furnishings during cleaning.

Use well-controlled brushing of duct surfaces in conjunction with contact vacuum cleaning to dislodge dust and other particles.

Use only soft-bristled brushes for fiberglass duct board and sheet metal ducts internally lined with fiberglass. (Although flex duct can also be cleaned using soft-bristled brushes, it can be more economical to simply replace accessible flex duct.)

Take care to protect the duct work, including sealing and re-insulating any access holes the service provider may have made or used so they are airtight.

EPA website
How to Prevent Duct Contamination

Whether or not you decide to have the air ducts in your home cleaned, committing to a good preventive maintenance program is essential to minimize duct contamination.

To prevent dirt from entering the system:

Use the highest efficiency air filter recommended by the manufacturer of your heating and cooling system.

Change filters regularly.

If your filters become clogged, change them more frequently.

Be sure you do not have any missing filters and that air cannot bypass filters through gaps around the filter holder.

When having your heating and cooling system maintained or checked for other reasons, be sure to ask the service provider to clean cooling coils and drain pans.

During construction or renovation work that produces dust in your home, seal off supply and return registers and do not operate the heating and cooling system until after cleaning up the dust.

Remove dust and vacuum your home regularly. (Use a high efficiency vacuum (HEPA) cleaner or the highest efficiency filter bags your vacuum cleaner can take. Vacuuming can increase the amount of dust in the air during and after vacuuming as well as in your ducts).

If your heating system includes in-duct humidification equipment, be sure to operate and maintain the humidifier strictly as recommended by the manufacturer.

Whether of not you decide to have the air ducts in your home cleaned, committing to a good preventive maintenance program is essential to minimize duct contamination.

To prevent ducts from becoming wet:

Moisture should not be present in ducts. Controlling moisture is the most effective way to prevent biological growth in air ducts.

Moisture can enter the duct system through leaks or if the system has been improperly installed or serviced. Research suggests that condensation (which occurs when a surface temperature is lower than the dew point temperature of the surrounding air) on or near cooling coils of air conditioning units is a major factor in moisture contamination of the system. The presence of condensation or high relative humidity is an important indicator of the potential for mold growth on any type of duct. Controlling moisture can often be difficult, but here are some steps you can take:

Promptly and properly repair any leaks or water damage.

Pay particular attention to cooling coils, which are designed to remove water from the air and can be a major source of moisture contamination of the system that can lead to mold growth. Make sure the condensate pan drains properly. The presence of substantial standing water and/or debris indicates a problem requiring immediate attention. Check any insulation near cooling coils for wet spots.

Make sure ducts are properly sealed and insulated in all non-air-conditioned spaces (e.g., attics and crawl spaces). This will help to prevent moisture due to condensation from entering the system and is important to make the system work as intended. To prevent water condensation, the heating and cooling system must be properly insulated.

If you are replacing your air conditioning system, make sure that the unit is the proper size for your needs and that all ducts are sealed at the joints. A unit that is too big will cycle on and off frequently, resulting in poor moisture removal, particularly in areas with high humidity. Also make sure that your new system is designed to manage condensation effectively.