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4 Signs of Mold in Air Ducts

Published: March 19, 2020

Even if you are diligent about keeping your HVAC system in good shape,

your home could have a hidden problem that is easy to overlook — moldy air ducts. Moldy air ducts are a health risk for your family, and mold remediation should be of particular concern if you live in a humid environment. Here are four signs of mold in your air ducts that you should watch out for.

1. A Musty Odor When Running Your HVAC

When mold is present in a large enough volume, it will begin to emit a distinctive smell. Many people describe the smell of mold as musty or earthy. The smell of mold may be unpleasant, but on the bright side it makes larger mold infestations easier to detect.

When you have mold buildup in your ducts,

the smell will usually be strongest while your HVAC system is running. This is because the air that comes from your ducts will pick up and carry more mold spores as the mold inside the ducts spreads. When your system isn’t running, spores will settle inside the ducts and the smell will be harder to notice.

2. Illness and Allergy Symptoms

By far the most significant risk of having mold in your ducts is the health effects it can cause for your family. While breathing mold spores can cause symptoms in virtually anyone, some people have an allergy to mold spores that makes them especially sensitive to moldy ducts. Likewise, mold can exacerbate the symptoms of anyone in your family with pre-existing respiratory problems.

Allergy symptoms

such as itchy, watery eyes; coughing and sneezing; and difficulty breathing can be signs of mold if they occur indoors, especially if they are more severe in rooms that are air-conditioned. In more serious cases, breathing mold spores can cause fatigue, nausea, vomiting and diarrhea, and confusion. Stop using your HVAC system until you’ve had it inspected for mold if you see these symptoms in your home.

3. Visible Mold on Air Ducts

Since the air from your HVAC system comes in contact with your vents first before it reaches the rooms in your home, it is not uncommon to see significant mold buildup on the vents. Spores will settle on your vents and appear as small spots that are usually black, green, or white in color. Even if you don’t see mold on the outside of your vents, you should remove them occasionally and check for mold growth on the duct-facing side.

Cleaning the mold off of your vents will naturally make them look much better, and may reduce illness and allergy symptoms since mold is no longer growing directly in the room. To clean mold off of a vent register, remove it and submerge it in water, and then add laundry detergent and let it soak. This is a good time to vacuum out the exposed duct to remove as much additional mold as possible.

4. Mold Inside Furnace or Air Conditioner

The same conditions that promote mold growth in your ducts are also present inside your furnace and air conditioner. Mold can grow on virtually any surface as long as it is in a dark and damp environment. The mold in your ducts may have originated from mold growth in these appliances that were spread through your ductwork as you used your HVAC.

The most common places to see mold growth

in an air conditioner are on the evaporator coils or in the drain pan beneath them. These components are frequently coated with condensation that can provide enough moisture for mold to flourish. You may see mold anywhere in your furnace as it heats and humidifies the air inside it.

Knowing the signs

of mold growth in your air ducts will allow you to get a duct cleaning early before the mold infestation spreads. Contact Service Tech, Inc., if you are in need of duct cleaning so you can enjoy the best possible air quality in your home.

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