A return vent (also called a return air grille) is a critical part of your HVAC system. While supply vents push conditioned air into your rooms, return vents pull air back into your system to be filtered, re-cooled or re-heated, and recirculated.

In short?

Supply blows air out. Return pulls it back in.

Over time, return vents collect massive amounts of dust, debris, allergens, hair, pet dander—even mold. Why? Because they’re sucking in all the air from your space—over and over, every single day.

If your return vent is dirty, your entire HVAC system is circulating contaminated air through your home or building. This affects your air quality, your allergies, and your system's efficiency.