Mold is a type of fungi that can grow both indoors and outdoors. It thrives in moist, warm environments and can be found in a variety of places, including HVAC systems. While mold is not necessarily harmful, it can cause a variety of health problems, including respiratory problems, skin irritation, and headaches.
There are a few ways that mold can get into an HVAC system. One way is through the air intake. If there is mold growing outside, it can be drawn into the system and circulated throughout the home. Another way is through the ductwork. If there is a leak in the ductwork, mold spores can enter the system and be distributed throughout the home.
The best way to prevent mold growth in an HVAC system is to keep the system clean and free of debris. The air intake should be regularly cleaned, and the ductwork should be inspected for leaks. Additionally, the humidity level in the home should be kept under control to prevent mold growth.
https://www.cdc.gov/mold/faqs.htm
https://www.epa.gov/mold/mold-cleanup-your-home
https://www.mayoclinic.org/diseases-conditions/molds/symptoms-causes/syc-20373973