How is my heating, ventilation, and air conditioning (HVAC) system related to indoor air quality?
Proper operation of the HVAC system is the backbone of any indoor air quality plan. Have a qualified professional inspect your HVAC system and ductwork regularly. Your thermostat should be set to a temperature that ensures regular system cycling for proper ventilation and dehumidification. Set the fan to the “AUTO” position instead of “ON” so that the fan does not run constantly. If the fan continues to run when the compressor shuts off, the outside air that it pulls in is not being dehumidified. Over time, the indoor relative humidity will increase and mold growth will begin. Microbial growth (including bacteria, mold, and algae) often occurs in the condensate drain pan, since this area receives a constant supply of moisture during the cooling season. This microbial growth can clog the drain line, resulting in an overflow that can damage underlying building materials. Inspect the drain pan regularly for signs of microbial growth and add chlorine bleach or an algaecide tablet if necess
