Signs of Mold in Air Ducts 

Table of Contents

Think you might have mold growing in your air ducts or A/C?

These are some of the most common concerns we hear—and things we actually see on the ground—from people in homes where we’ve found mold in air ducts and A/C units.

1. Coughing, Respiratory Issues

Your HVAC system is the “lungs of your home.” If there’s mold growing in any part of it, that mold is eventually going to be spread around the whole whole home. That doesn’t mean mold will be visibly growing everywhere in the house, but it does mean that mold spores will be floating and circulating throughout the home, which you will be breathing in daily. That causes coughing and other respiratory issues, according to the CDC and many, many homeowners we’ve personally helped across the Tampa Bay area.

2. Musty Odor

A musty smell in your air vents is a strong indication of mold. This smell, earthy or damp, is usually more prominent while the air conditioning is running which ultimately indicates mold growth in your HVAC system. That said, this must be addressed immediately to prevent health issues and mold spread.

3. Visible Mold Growth

Visible mold growth is another obvious sign. Mold can be black, green, white, or pink and appears fuzzy or slimy. Mold growth can usually be seen in vent covers, ducts, and HVAC systems. If you notice this, you should fix the issue right away and conduct regular checks, especially in humid environments. Mold can quickly spread throughout your house, so clean and remove it immediately.

4. Black Dust or Dark Streaks

Black dust or dark streaks around air vents is a sign that indicates mold. This black dust around vents is mold spores, not dirt or soot. While most people wipe this dust away, it usually returns again shortly indicating mold. Cleaning your vents regularly and looking for black dust can help detect mold early.

Ways to Prevent Mold in Air Vents

To prevent the growth of mold in air vents, it is important to maintain cleanliness of your HVAC system and effectively control moisture levels. Stick to a consistent maintenance routine, use dehumidifiers to maintain humidity levels within the range of 30-50%, and for proper ventilation.

Address leaks quickly, and change A/C filters often. For more in-depth advice, download the extensive MoldEBook by Brandon Faust, which covers everything you need to know about proper maintenance and mold prevention.

Call Mold Solutions for a Free Environmental Consultation.

More Than 175 Five-Star Reviews

Stephanie K.
Stephanie K.
Local Guide · 60 reviews · 35 photos
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"Out of all of the options in the area, I’m so glad I went with Mold Solutions. They were the only ones that can thoroughly handle my entire problem, including the air conditioning ducts where other companies were telling me I needed 3 to 4 different service people with different bills all coming to my house at different times costing me tons of money. They got everything done in one day. I felt the difference in my health immediately after they finished." — 5-Star Google Review
John E.
John E.
21 reviews · 13 photos
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I'll start by saying Alisha from the word go was fantastic and brandon when he came out put me at ease. See I got taken by another company for thousands of dollars .The team hats off to you Devin, Heather,Monica thank you for doing such a caring job and giving us back are home in a condition we could be safe in and start the build back process. Devin and Alisha thank you for responding to every question we had . I will recommend you to whomever has to go through this type of horrible experience. You guys handled it with compassion and integrity and that in itself is a dieing trait So many thanks to you all....
Linda. M
Linda. M
6 reviews · 5 photos
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Mold solutions just remediated mold in my air handler and ductwork throughout my home. They were very thorough. I was impressed with their knowledge of mycotoxins from mold and the seriousness of mold. All of the staff that I interacted with was patient, friendly, helpful and efficient. They kept me informed and I was super happy that the entire home was dry fogged with pet friendly ingredients. My two cats and I had to go out on the patio for 3 hours as the dry fog did it's thing. They kept me informed and let me know when it was perfectly safe to go back inside. Trustworthy, efficient and nice.
Mold Solutions is Tampa Bay's Highest-Rated Mold Remediation Company!

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Mold Solutions is a health-centric mold removal and remediation firm founded by Brandon Faust (🔗) and servicing the Greater Tampa Bay area.

Mold Solutions, LLC
1536 S Missouri Ave Ste. A, Clearwater, FL 33756 (🔗)