You see ads for air duct cleaning that promise purer home air and more efficient operation of your HVAC. But is air duct cleaning really needed? Let’s see what the experts say.
Your system and dust accumulation
The air duct system is the series of large tubes that draw new air to a home’s HVAC machinery through intake grills and send treated air back to the interior of the house through return grills.
Dust is more likely to accumulate on intake grills than on return air ducts and grills. Your air filters should catch the vast majority of contaminants at the intake, which means the treated air that is returned to your rooms is clean.
How air duct cleaning works
Air duct cleaning services use a specialized vacuum and brushes to clean the inside of your ducts throughout the house to remove dust and other contaminants. The servicers claim that such cleaning will improve the air quality inside your home as well as the operating efficiency of your HVAC system. The air quality claims are particularly appealing to family members suffering from allergies or asthma.
Where’s the evidence?
Real evidence of these claims is scant, however, particularly the air quality claim. Any dust present in duct work usually clings there and doesn’t blow out into the room. Government studies in both the U.S. and Canada find little evidence of improved indoor air quality with duct cleaning, or any significant improvement in HVAC operating efficiency. In fact, air quality immediately after cleaning could be worse temporarily because of dust stirred up during the cleaning.
Experts see no harm in duct cleaning but say it isn’t generally necessary for routine maintenance.
Prevention is the best cure
The best way to prevent dirty ductwork is to keep your intake filters clean and to change them regularly. Catching the contaminants at the point of entry does far more to keep ducts clean than hiring an air duct cleaning service. For families battling respiratory ailments, a system employing HEPA air filters could be a much bigger help.
When might air duct cleaning be worthwhile?
Air duct cleaning might make sense in certain situations, such as when ducts are infested with animals or mold is present. If mold in ductwork is a problem, however, you should also have your HVAC system evaluated by a professional to determine what is causing the problem.
Another scenario where cleaning ducts might be appropriate is where intake and return air registers were left uncovered during interior remodeling and renovation, allowing significant dust to accumulate in ductwork.
Related – Benefits of Home Air Purifiers