“The air ducts in your home just need to be cleaned once. The ducts really just get dirty when the home is being built, due to drywall dust. Otherwise, unless there are problems, they don’t need to be routinely cleaned,” explains Tom Eppers, co-owner, Dowe & Wagner, a heating, ventilation, and air-conditioning (HVAC) company serving residential and commercial customers in Illinois and Wisconsin.
He adds that using a high-quality air filter can improve the quality of indoor air, without needing to clean the ducts (which are the tubular passageways for the home’s airflow).
The Environmental Protection Agency (EPA) agrees that some circumstances may warrant duct cleaning, including substantial visible mold growth inside the ducts and other components of the HVAC system. The EPA defines duct cleaning as “cleaning of various system components of forced air systems, including the supply and return air ducts and registers, grilles and diffusers, heat exchangers, drip pans, fan motor housing, and the air handling housing.
“Many sections of your heating and cooling system may not be accessible for a visible inspection, so ask the service provider to show you any mold they find. If you have insulated air ducts, and the insulation gets wet or moldy, it cannot be effectively cleaned, and should be removed and replaced,” the EPA says. “Prior to any cleaning, retrofitting, or replacing of your ducts, the cause of mold must be corrected, or the problem will likely recur.”
The EPA adds, “Some research suggests that cleaning heating and cooling system components (such as cooling coils, fans, and heat exchangers) may improve the efficiency of your system, resulting in a longer operating life, as well as some energy and maintenance cost savings.
“Whether or not you decide to have the air ducts in your home cleaned, preventing water and dirt from entering the system is the most effective way to prevent contamination.”