Why Do My Air Ducts Have Mold? Anytime you see mold in your ductwork, know that some factors could have been responsible for its presence. For instance, it can exist in vents that have warm as well as moisture temperatures. Generally speaking, if the environment is warm and humid, always expect mold to grow there. It is also the same for HVAC systems that lack proper ventilation. This is why regular and consistent duct and vent cleaning is required. With such, you have a fair chance of eliminating mold and all the threats that it can pose. These could be breathing difficulty, sneezing, coughing and others. Apart from mold growing in dirty vents, there are still some problems which lack of maintenance can bring. For instance, you will have to struggle with the problem of improper air flow. This happens when some rooms are colder than others. Poor duct and vent can also lead to such issue. Also, you will still experience unpleasant odor in your home. This is probably one reason why you need to hire a company that can render air duct cleaning service. In summary, enjoying fresh and healthy air doesn’t require much. It is all about hiring a company that can help out in rendering top duct cleaning services. This is the only way your vent can be clean at all times.