HVAC System Hygiene – Duct Cleaning by Advanced Indoor Air Quality Care
Q: Why Should You Get Your Air Ducts Cleaned?
A: Because they get dirty!
In addition to normal accumulations of dust and dirt found in all homes through regular use, there are several other factors that can increase the need for air duct cleaning:
- Occupants with allergies or asthma
- Cigarette or cigar smoke
- Water contamination or damage to the home / HVAC system
- Home renovation or remodeling projects
Some occupants are more sensitive to these contaminants than others. Allergy and asthma sufferers, as well as young children and the elderly tend to be more susceptible to the types of poor indoor air quality that air duct cleaning can help to address.
Air Duct Cleaning Services – What you Need to Know
Air duct cleaning is a misnomer. In actuality, the entire HVAC system should be cleaned. Failure to clean all components of the system can result in re-contamination of the entire system, thus minimizing the benefits of cleaning. Just as you wouldn’t only clean half of your living room floor, you also would not want to clean only part of your heating, ventilation and air conditioning (HVAC) system. NADCA recommends cleaning the entire HVAC system, including the following components:
- Drain pan
- Air plenum
- Blower motor and assembly
- Heat exchanger
- Air Filter
- Air Cleaner
Proper HVAC Cleaning Process
There are two key components to HVAC cleaning – breaking contaminants loose, and collection of contaminants.
Breaking Contaminants Lose:
Properly cleaning HVAC systems requires removing the sources of contamination. Source removal begins with use of one or more agitation devices designed to loosen contaminants from the surfaces within the heating and air-conditioning system. Examples of agitation devices include brushes, air whips, and compressed air nozzles or “skipper balls.” Agitation can also be achieved through hand-brushing or contact vacuuming.
Collection of Contaminants:
During cleaning, the entire HVAC system is placed under continuous negative pressure (vacuum) to prevent the spread of contaminants. Continuous negative pressure allows very fine particles to be removed from the system as they become airborne, ensuring that these particles are not released into the living space when the system is turned on after cleaning. This negative pressure also serves to extract the loosened contaminants, which are collected and removed from your home.
System Access HVAC system cleaning is not a complex process, but each job is unique. Where possible, access to duct interiors should be made through existing openings such as supply diffusers, return grills, duct end caps, and existing service openings. Cleaning technicians may need to cut access holes in the duct work in order to reach inside with various cleaning tools. Creation of these service openings, and their subsequent closure, requires craftsmanship and professional skills.
Duct Cleaning Equipment Requirements:
There is a wide variety of equipment available to HVAC cleaning professionals. Both truck-mounted and portable vacuums can be used to stop the spread of contaminants and get the system cleaned to the NADCA Standard.
The Use of Antimicrobial Chemicals in Air Duct Cleaning:
Antimicrobial chemicals include sanitizers, disinfectants and deodorizers that can be applied to non-porous surfaces in HVAC systems to address microbial contamination and help control odors. Only chemicals registered with the United States Environmental Protection Agency (EPA) can be used. These products should only be considered after mechanical surface cleaning has been performed and if the need for such treatment.