According to the EPA, the main purpose of an HVAC system is to help maintain good indoor air quality through adequate ventilation with filtration, while providing thermal comfort.
In most of the country that’s a seasonal concern. In South Florida it’s a year-round reality. Your AC system is constantly circulating the air in your home or building — filtering it, cooling it, and controlling humidity. When it’s working well, it’s your best defense against airborne pollutants, mold spores, and excess moisture. When it’s neglected, it becomes the problem.
A dirty or poorly maintained AC system doesn’t just cool your space less efficiently — it actively degrades the air you breathe. Some common issues could be:
Mold in the drain pan and evaporator coils — Moisture collects in these areas naturally. Without regular maintenance, mold and bacteria can grow and get pushed directly into your living space through the air supply.
Clogged or dirty filters — A filter that hasn’t been changed circulates dust, mold spores, pet dander, and other particles back into your air instead of trapping them.
Contaminated ductwork — Over time, dust, debris, and biological growth can accumulate inside ducts and get distributed throughout the building every time the system runs.
Humidity imbalance — A system that’s oversized, undersized, or not functioning correctly can fail to control indoor humidity — the root cause of most mold problems in South Florida.
Browse our HVAC & AC topics below
In South Florida, humidity control is just as important as temperature control. Learn how an AC system manages moisture, what happens when it doesn’t, and what to do about it.
learn more
Not all air filters are created equal. Learn what MERV ratings actually mean, how often to change filters in South Florida’s climate, and which filters make a real difference for your indoor air.
Your ducts are the highway your air travels through. Learn how duct condition affects your indoor air quality, signs your ducts may need attention, and what duct cleaning actually involves.
Mold in an AC system is one of the most common — and most overlooked — indoor air quality problems in South Florida. Learn where it grows, how to spot it, and what to do about it.
We’re here to help. Whether you’re trying to learn about pollutants in your home or workplace, or just want to point us toward a topic you’d like us to cover — we’d love to hear from you.
South Florida Indoor Air is an independent educational resource dedicated to helping our community breathe better and make informed decisions about the air inside their spaces.