Yes, HVAC systems and ducts often become contaminated with mold. These systems provide a dark and often moist environment, which can be conducive to mold growth if there is a source of moisture. Mold can grow on the surfaces of air conditioning components such as coils, drip pans, and insulation. Additionally, if there are any leaks or condensation issues within the system or the ductwork, it can create a breeding ground for mold. Contaminated AC systems can then distribute mold spores throughout the indoor air, potentially leading to mold growth in other areas of the building. This can result in poor indoor air quality and potential health issues for the occupants