Dust in our HVAC systems comes from all different types of sources. We may have household dust, construction dust, pet hair and dandruff, pieces of food in our ducts. Most of these are organic and will be eaten by germs, bacteria, insects, etc. And when the system turns on, the power of the air stream will detach some of these small dust pieces with microbes and contaminate the indoor air. Who wants to inhale all that stuff? Certainly not you! And neither is your HVAC system. When dust covers some crucial components it creates an insulation layer that prevents heat exchange and these components won’t be properly cooled (heating coil) or warmed (AC Coil). This may cause premature equipment failure.