Clean AC ducts can mean healthier indoor air quality and a cleaner house. Consider this fact: The entire air volume in your home circulates through your ductwork five to seven times every day. Whatever’s lurking inside your ducts ends up in your breathing air and vice versa.
Although careful housekeeping can eliminate allergens and contaminants on the surfaces you can see, the inside of ductwork is a dark, inaccessible maze that may accumulate years of airborne particulates, chemical residue, mold and even pests like insects and rodents.
Clean AC ducts are only one element of a successful strategy to safeguard indoor air and duct cleaning isn’t called for in every case. Where contamination is verified, however, duct cleaning can provide measurable improvements in both household air and efficient cooling and heating.
Dust to Dust
Allergic responses can result from many elements in household air. Common dust, for example, is not merely common, it’s abundant. Studies show the average home generates a whopping 40 pounds of dust per year. Dust consists of more than just one ingredient. Lint, dirt, skin flakes, dust mites and pet dander are all included. Most dust is buoyant. When it’s not briefly settling on household surfaces, it’s stirred up in the air by normal household activities and sucked into your HVAC ductwork. In between “on” cycles when the blower fan is off, these particulates settle inside the ducts and begin to accumulate in layers. When air circulation resumes, some dust is reintroduced into the household air while still other dust adds to the collection in the ductwork. Over years of this process, it’s not hard to understand how a considerable volume of dust can gather in the network of ducts that extend through your home.
What You Don't See
Dust, at least, is an annoyance you can usually see. Many of the constituents of indoor air pollution, however, are too small to be seen with the naked eye. Unlike dust, most of these irritants have their origins outdoors but concentrate and multiply in the enclosed, air-tight environment of a modern energy-efficient home. Microscopic mold spores, for example, can be swept into your home every time an exterior door or window is opened and pulled into the air conditioning ducts. Moisture from condensation and the dark environment inside ducts provide a perfect breeding ground for a mold colony. Once established in the ductwork, mold continues to disperse millions of spores into the air circulated throughout your home. Mold spores are a known source of allergic responses, including respiratory symptoms, and have been implicated in the development of childhood asthma.
Pollen is another outdoor microorganism that may migrate inside and accumulate in AC ducts. Familiar hay fever symptoms that persist even when the outdoor pollen season is over may be a sign of pollen contamination in ductwork that's being continually recirculated in your household air.
What You Can Do
The solution to suspected duct contamination is two-fold. First, an accurate evaluation of the condition of your ductwork should be performed by a reputable HVAC professional. This should be an established company in your community with the expertise and track record to give you an accurate, unbiased appraisal. If corrective action is required, the procedure to clean AC ducts should be carried out in strict accordance with procedures that conform with recognized industry standards.
Most ductwork is inaccessible to the average homeowner. Pointing a flashlight into an air conditioning vent can’t really tell you the true state of the several hundred feet of ductwork comprising the network that circulates air throughout your home. A competent duct inspection will include opening and visually inspecting ductwork in areas such as the attic and the crawl space beneath your home. Some inspectors may utilize technology like micro-video cameras on fiber optic cables to look deep into ducts for sources of contamination. The technician will also examine system components such as the blower fan, coils and filters for wear and tear and other telltale signs that the system is carrying a load of contaminants.
If mold is suspected, samples of any suspicious accumulations inside the ducts will be taken and tested to verify the presence of mold and identify the type. Other factors a professional inspector will look for include any evidence of past or present water contamination and indications that insects or vermin have inhabited the ducts. All of these factors must be taken into consideration when the decision is made to recommend a procedure to clean AC ducts.
The Cleaning Process
A professional procedure that leads to clean AC ducts can be divided into two steps: dislodging contaminants and collecting them. Before the technician can do that, however, he or she first has to gain access to the dirt, dust and other contaminants in your ducts.
Getting to the Source
Where it's feasible, duct cleaning technicians access the inside of the ducts through existing routes. These include removable components such as grills, duct end caps, air diffusers and common service access openings that exist in any system. Components will be removed to perform the cleaning, then properly reinstalled and sealed.
In some cases, spans of ductwork may not incorporate removable components nor provide any existing access points. In these scenarios, the technicians may cut small access holes in the ductwork to insert the specialized tools used to clean AC ducts. A reputable duct cleaning contractor employs technicians with the experience and craftsmanship to create these openings accurately, then properly seal them after the duct cleaning procedure is finished.
Duct contamination, whether in the form of common dust and dirt or microorganisms like mold, has frequently been in place for long periods of time, often years, before a process to clean AC ducts is initiated. Specialized techniques to loosen and dislodge these accumulations effectively are required to ensure that the procedure conforms with industry cleaning standards. A professional duct cleaning provider will come well-prepared with agitation devices including soft-bristle power brushes, air whips, compressed air guns and other tools capable of breaking loose stubborn accumulations deep inside the ducts. Where required, simple hand-brushing and contact vacuuming is also used.
After the contaminants have been dislodged from the interior duct surfaces, they must be removed from the ducts and disposed of. This is a job for experienced, properly-equipped technicians. The process must be carried out in a manner that prevents duct contaminants from infiltrating into your home as they're being removed.
Industry-recognized procedures call for the system to be placed under negative air pressure for the removal process. A professional duct cleaning outfit will use a powerful vacuum that may be mounted on a truck outside or brought into your home. After connection to your duct system, the vacuum will be used to induce negative pressure in the ducts as contaminants are being removed from various access points. This powerful vacuum force prevents the infiltration of contaminants into your interior environment and also ensures the final effectiveness of the cleaning process as it sucks residual airborne dust out of the ductwork.
The vacuum exhaust stream is filtered by high-efficiency HEPA filtration that captures particles smaller than 0.3 microns to safeguard your air quality. Removed contaminants will be sealed in bags, removed from your property and disposed of in accordance with local sanitation and environmental ordinances.
In addition to cleaning the ductwork channels, a comprehensive process to clean AC ducts also includes cleaning mechanical components that occupy the airstream in the duct system. These include the blower fan and the evaporator coil in the air handler, as well as room registers and grills. Of course, new air filters will also be installed after the ducts are cleaned.
After the Cleaning
Once you have clean AC ducts, any nonporous internal duct surfaces where mold or other microbial growth was detected may be treated with EPA-approved disinfectants and sanitizers. If musty odors have been a problem, the pros may also apply deodorants to the interior of the ducts.
Any components removed to facilitate cleaning will be reinstalled and access holes will be closed and sealed to prevent air leakage. Finally, the duct cleaning contractor will restart the system and verify proper air circulation to all rooms in the home.
Comfort24-7 is your comprehensive interior comfort and air quality provider in Chicago, Northwest Indiana and Southwest Michigan. Ask us for more about advanced procedures to clean AC ducts and help keep your household air contaminant-free and healthy.