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What Causes Mold in Air Ducts?

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Untreated mold can cause serious health problems. When you have mold in your air ducts, it could go undetected for weeks, causing health problems and even structural damage.

What causes mold in air ducts, and how can you prevent it? This post will teach you the signs of mold, what causes it, and when to call Bowie’s expert air duct cleaning professionals at S&L Air Conditioning and Heating in Bowie, MD.

Bowie's expert air duct cleaning

Causes of Mold in Air Ducts

When learning what causes mold in air ducts, there are two main factors: moisture and dust. 

Areas with high humidity tend to have more frequent issues with mold. When warm, humid air from outside meets the cool air inside your air conditioner, condensation forms. Mold spores thrive in the damp, dark environment of your air ducts. 

It’s normal for pet dander, dead skin cells, and other small particles to settle in your air ducts. Mold spores feed off these particles, helping the infestation to thrive. As mold grows inside the air ducts, your indoor air quality will dramatically diminish.

A surprising cause of mold is an oversized air conditioner. An air conditioner that is too powerful for the space will quickly turn on and off without dehumidifying the air as it should. A professional HVAC technician can help you determine if you have the right size air conditioner for your home.

Identifying Signs of Mold

Your nose may alert you to the presence of mold before anything else. A musty odor coming from your vents indicates mold and mildew. If you only notice the smell when your HVAC unit is running, that’s a sure sign of mold.

When mold is present in your air ducts, spores circulate throughout your home and cause serious health issues. If your seasonal allergies are suddenly worse, or if you experience new symptoms like itchy eyes, runny nose, or headaches, it could be from mold exposure.

Examine the inside of your air conditioner and the vents to check for visible mold. If you see small black spots, you should immediately call a professional to thoroughly clean your unit. By the time you see visible mold, you could have a serious mold infestation.

Ways to Prevent Mold Growth

If you neglect your HVAC unit until it has an advanced mold problem, you will end up spending hundreds on repair costs, mold remediation, and allergy treatments. Taking good care of your HVAC unit can help prevent mold growth and extend the life of your unit. 

Change the Filter

A clean filter helps your HVAC unit remove contaminants from the air and prevents them from circulating throughout your home. Replacing the filter every two to three months will help improve your indoor air quality and slow mold growth.

Inspect the Ductwork

Ductwork is delicate and easily sustains damage from extreme weather, water leaks, and rodents. Damaged air ducts allow hot outside air, dirt, and small animals to enter the ductwork. When you schedule annual HVAC maintenance service, a technician will inspect the ductwork for signs of damage.

Keep Indoor Humidity Low

If your indoor humidity level is above 50%, it creates ideal conditions for mold growth. A hygrometer is an inexpensive tool to check the humidity level inside your home. A dehumidifier can lower humidity in areas above 50%, like bathrooms and basements. 

If your entire home has a consistently high moisture level, consider installing a whole home dehumidifier on your HVAC unit.

Maintain the Roof

A dilapidated roof causes water leaks, which allow rainwater to enter your attic. If your ductwork is in the attic, it can become damaged from the overabundance of moisture before you even realize there is a problem. Maintaining your roof by replacing and securing the shingles will keep moisture out of your attic and mold out of your air ducts.

Professional Mold Removal

When you take measures to prevent mold before it forms, you keep your family and your home safe from mold forming in your air ducts. If mold is already present, the best way to ensure it gets thoroughly cleaned from your HVAC system is by scheduling professional HVAC cleaning. Not all household cleaners thoroughly kill mold spores, which will cause the mold to quickly regrow.S&L Air Conditioning and Heating in Bowie, MD, knows what causes mold in air ducts and how to completely eradicate mold. Our service includes ac coil cleaning to remove mold inside your unit as well. Call 301-923-4571 to schedule service with our expert team.

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