Did you know your HVAC system is a perfect breeding ground for microbial contamination…mold?  The evaporator coil provides every needed element for mold growth which then spreads through your ventilation system when the blower turns on.   Mold is ever present in our air but when it finds the coil it finds the perfect place to flourish, food (dust/dirt) and water (condensation).  Over time a “BIOFILM” develops on the fin surfaces.  Biofilm is a layer of microbial growth that can affect your energy use, equipment longevity, and indoor air quality.  This is why equipment manufacturers, industry organizations and the US Department of Energy recommend that you inspect and clean your coils regularly.  People sensitive to mold spores/ particulates will probably “feel” the mold first but we all have them.  So when someone asks if you “got mold?” you probably do.