Mold in air ducts can cause allergic reactions

Mold is a living organism that breaks down dead materials and return nutrients to the environment. Mold grows by digesting plant and animal matter, and spreads by releasing lightweight spores that travel through the air.  Mold is harmless outdoors, but when it begins to grow indoors it can be a problem.

Most people are exposed to some mold every day without suffering any side effects, but people with mold allergies can have a reaction if exposed to too much mold. Some of the symptoms of mold allergies include wheezing, stuffy or runny nose, rashes or hives, and itchy, watery eyes. Potential health problems and symptoms often associated with exposure to mold include allergic reactions, asthma and other respiratory complaints.

Unfortunately, mold can grow inside air ducts if moisture is allowed to settle into place. If you have mold or spores in your ducts, the blast of air from the heating or cooling system can set it into motion. The EPA suggests having your ducts clean if the surface of your ducts, or any other components on your heating and cooling system, have visible mold, but many areas of your heating and cooling system can be contaminated by mold and may not be immediately visible.

Your air conditioning and heating systems can also serve as an amplified breeding ground for mold. Air intakes are a potential source of contamination because of standing water and organic debris near that water. The inside components of your air conditioner can also breed mold because of the humidification systems, the cooling coils and the condensate drain pan.

San Antonio air duct cleaner  Dennis Mollgaard Jr., owner of Tiger Services, said he often finds mold in air conditioning systems.  Southern cities like San Antonio may be particularly prone to this problem, Mollgaard said, because of the heat and humidity.  If someone in the household has an allergy, mold in ductwork on in the HVAC system needs to be cleaned by a qualified expert.

After mold is cleaned from their ducts, inspecting the system at least once a year for mold growth and any other contaminants can not only save you money on your heating and cooling cost, it can help you put a stop to any contamination inside your ducts.

There is no way to eliminate all mold and spores from your home, but you can control the growth of mold by eliminating the moisture and cleaning mold and spores from your ducts. Check the humidity levels in your home, and make sure they are consistently above 50 percent.



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In addition to this buildup, contractors found a dead animal in this member's ductwork. (Photo courtesy of Angie’s List member Mariah J. of Taylors, S.C.)
In addition to this buildup, contractors found a dead animal in this member's ductwork. (Photo courtesy of Angie’s List member Mariah J. of Taylors, S.C.)

Out of sight and out of mind, ductwork can quietly and quickly contribute to poor indoor air quality, degrade health, and affect HVAC system efficiency. You can avoid ductwork contamination with these expert tips.


I have awful allergies and wonder if maybe my air ducts need replaceing. Would like a reputable company in Housotn, Texas

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