Mold and Your HVAC System

July 25, 2023


Mold can be a significant detractor from the quality of your home’s indoor air. Learning how mold can affect your HVAC system and the best solutions to eliminate it will protect your home comfort system. If you have concerns about your indoor air quality or mold growth affecting your ducts or HVAC equipment, contact an HVAC specialist to explore your options for improving indoor air quality.

Where Mold Can Grow

Mold and mildew can grow and spread quickly in areas where there is excess moisture and heat. Thus, areas that are exposed to consistently moist and warm conditions are at the highest risk. As your air conditioner works, it removes humidity from the air. This can cause moisture to accumulate on the coils; excess moisture is generally funneled into a drain or drip pan. However, these areas are prime places for encouraging mold growth. Check and clean your air conditioner’s coils, drain and drip pan periodically to prevent mold growth or catch it in its early stages. Additionally, check the outdoor components of your air conditioner during hot, humid weather. If dirt and debris build up around your condenser, they can harbor moisture and provide the perfect environment for mold growth. Finally, mold can sometimes accumulate inside the ductwork of your home, especially if you don’t run your air conditioner during very humid days or your air conditioner cannot adequately cool and dehumidify your home. A thorough inspection of your air conditioner and ductwork by an HVAC specialist can help you identify any problem areas that require attention.

How Mold Affects Indoor Air Quality

Mold growth that occurs on or near your HVAC system and ductwork can negatively affect the air quality in your home. As mold reproduces, it releases spores into the air. These spores can then be recirculated through your home via your HVAC system. Mold spores are a common allergen, sometimes causing symptoms that include congestion, coughing, wheezing, and watery or itchy eyes. Prolonged mold exposure can also cause headaches, irritability, and trouble sleeping. If your HVAC system has been affected by mold, improving your indoor air quality requires several steps. First, your HVAC system and ductwork should be professionally cleaned to eliminate any mold growth that is present. Antifungal chemicals can be used if necessary to inhibit any future growth. If your air conditioner’s drain and drip pan are not properly designed to funnel water away from the system, your HVAC specialist can make modifications to prevent the accumulation of excess moisture. Changing your furnace filter regularly can help to trap any mold spores that could otherwise circulate through your home. A more advanced air filtration system, such as an electronic air cleaner or UV lamp, can also be installed to further improve indoor air quality.

Mold and other allergens can affect your comfort at home, as well as limit the lifetime and efficiency of your HVAC system. Take a look through our website to learn more about improving your indoor air quality and protecting your home and your comfort system from mold. You can find more heating and cooling tips and information on our blog!

Last Updated: April 11, 2024