Indoor Air Quality (IAQ) is a growing health concern for many individuals. With so many indoor pollutants creating an unhealthy environment and high efficiency heating, ventilation and air conditioning equipment bringing in limited amounts of outdoor air, cleaning your air ducts is one of the major facets in preventing indoor air pollution.
Research by the U.S. EPA has demonstrated that HVAC system cleaning may allow systems to run more efficiently by removing debris from sensitive mechanical components. Clean, efficient systems are less likely to break down, have a longer life span, and will operate more effectively than dirty systems.
The ABCs of Duct Cleaning
Duct cleaning involves more than just vacuuming the diffusers and changing the air filters, there is a step by step process that a certified duct cleaner must follow. Some of the key areas are as follows:
• Determine what type of ductwork you have, sheet metal or fiberglass duct board.
• Will they clean the heat exchanger, cooling coil, blower fan assembly, condensate pan and drain?
• Will the coils be cleaned with chemicals or a vacuum and contact brush?
• (Cleaning the cooling coils is required by the NADCA Standard - Assessment, Cleaning & Restoration of HVAC Systems (ACR). However, some state regulations specify that only licensed HVAC mechanical contractors may clean cooling coils. Be certain to ask your NADCA member company representative if his/her company will clean the coils of your HVAC system, and by which method.)
• What will they use to clean the ductwork, truck-mounted equipment or portable equipment? (Truck-mounted vacuums are more powerful, but portable units will allow the contractor to reach certain areas more easily. Both are approved systems.)
• All vacuum units should be attached to a collection device for safe containment prior to disposal. Any vacuum collection device which exhausts indoors must be HEPA (high efficiency particulate arrestance) filtered.
The contractor will place the system under negative pressure, through the use of a specialized vacuum. The vacuum draws air through the system while special brushes and other devices, such as air whips and “skipper balls”, are inserted into the ducts to dislodge any debris that might be stuck to interior surfaces. The debris will travel down the ducts to the vacuum, which removes it from the system and the home.
Hiring a Qualified Contractor
Air duct cleaning is a growing business, and selecting a qualified, experienced professional may be a daunting task the first time you do it. Conducting some research prior to interviewing contractors is worh the time, so that you know what to look for when making your selection. The included guidelines will help to ensure that the contractor you hire is a reputable mechanic who will do an effective job.
Make sure that the cleaner you are considering is a member of the National Air Duct Cleaners Association, or NADCA. This organization provides standards for acceptable methods of cleaning for the association, in addition to training and certification in cleaning (ASCS), inspection (CVI), and mold remediation (VSMR) for contractors in the United States and Canada. Their website will help you locate an approved member of their group by postal code or by state.
Select several members from the list generated from the site, and narrow your choices by location, required certifications, or how long they have been members. Find out how long each air duct cleaner has been in business as a duct cleaner. Find out how familiar they are with the specific system your home has.
Some other questions and tips:
• Ask if the company is in good standing with your local Better Business Bureau.
• Get proof that the company is properly licensed and adequately insured.
• Verify that the company is certified by NADCA to perform HVAC system cleaning.
• Make sure that the company is going to clean and visually inspect all of the air ducts and related system components.
• Avoid advertisements for "$99 whole-house specials" and other sales gimmicks.
• Ask if the company has the right equipment to effectively perform cleaning, and if the company has done work in homes similar to yours.
• Get references from local clients.
• Ask them how long it will take to clean the system. It will vary depending on the size and complexity of your HVAC system.
• Ask if they will be using sanitizers. Sanitizers are anti-microbial chemicals applied to the interior surface of the air ducts, designed to control microbial contamination. Before any sanitizers are used, the system should be thoroughly cleaned. It is critical that any anti-microbial treatment used in your system be EPA registered for the intended use in HVAC systems. Ask to see the Material Safety Data Sheet (MSDS) for the chemicals they intend to use. If you are still concerned, call the EPA at 1-800-438-4318. There are no EPA registered anti-microbial products for use on porous system surfaces – such as fiberglass duct board or fiberglass-lined surfaces.
How Often to Clean your Ducts
There is no standard for the frequency of cleaning , but it mainly depends on the preference of the home owner. Some of the things that may lead a home owner to consider more frequent cleaning include:
• Smokers in the household.
• Pets that shed high amounts of hair and dander.
• Water contamination or damage to the home or HVAC system.
• Residents with allergies or asthma who might benefit from a reduction in the amount of indoor air pollutants in the home’s HVAC system.
• After home renovations or remodeling.
• Prior to occupancy of a new home.
Finally, inspect your system to verify that it is cleaned. The best way to determine if the HVAC system cleaning was effective is to perform a visual inspection of the system before and after cleaning. If any dust or debris can be seen during the visual inspection, the system should not be considered cleaned. The contractor should be willing to allow you to use his inspection tools such as mirrors, lights, and cameras to see that the ductwork is clean. If they won’t, they’re probably hiding something.
Cleaning ductwork will help keep your home cleaner and more energy efficient, while also protecting you and your family from allergens and irritating dust.
