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HVAC Mold Removal

How To Remove Mold From Air Conditioner Ducts

HVAC systems have come a long way since first introduced as a method for efficiently heating and cooling buildings. We now have units of all sizes and types bringing comfortable living to individuals everywhere. Unfortunately, these systems can be sabotaged by mold colonies growing in the ductwork. The intake and returns for air can be contaminated by mold spores, creating poor air quality and an unpleasant odor.

Dealing with mold in HVAC ductwork can be a challenge.  In this post, we’ll share how to effectively remove mold from air conditioner ducts.

Identifying the Presence of Mold in Air Conditioner Ducts

You will probably smell a problem with mold before you see it. Mold growth brings a musty odor that some compare to the smell of a wet dog. If there is growth in the ductwork, you may be able to smell the stink in one room or several adjoining rooms. As the colony starts to expand, you may see evidence of mold through black, green, or brown spots creeping out of your air vents in the room where the ductwork attaches. You won’t see the individual mold spores unless you have special equipment, and it can take a while before you see the signs. However, the smell often starts long before you see the damage.

man inspecting hvac for mold

Realizing the Cause of Mold in Air Conditioning

While mold can grow anywhere, air conditioning ductwork provides a nice warm, dark location for growth. Mold requires oxygen and moisture, and it feeds on organic matter and debris. Ductwork has all of these components. Water vapor is created when cold air with a high moisture content passes through warmer ductwork passages. Rather than evaporating and dissipating outside, the vapor collects into water droplets that coat the interior of the duct system. This becomes the perfect place for mold to root. The dust, pollen, dead skin, cells, and pet dander flowing through the air provide an endless nutrition source for the growth.

how to clean mold from air conditioner

Signs of Mold in Your HVAC System

Each person’s residence may have one or more of the common signs of mold. In an HVAC system, you will need to start with your sense of smell before moving on to visible evidence. Here are a few of the common conditions that indicate mold is growing in the home:

  1. A strong musty odor that is in one or more rooms of the home
  2. Eye, nose, and throat irritation occurring when the HVAC unit is running
  3. Continually experiencing allergy symptoms like rashes, watery eyes, or a runny nose
  4. Unexplainable hePLEASEDELETEches that resolve outside the home
  5. Feelings of dizziness, fatigue, or nausea when at home
  6. Mold growth spots around intake vents or unit drip pans

signs of mold in hvac

It is more likely that you will smell mold if you live in a warmer, humid climate and have the air conditioning running. You don’t have to wait until you actually see signs of growth or damage to address the problem. You may be able to tackle a small instance of mold growth on your own, but bringing in professional help is often the best solution. There are some natural DIY techniques that can help remove the mold, but if your problem is severe, the Environmental Protection Agency recommends using a professional remediation service. Inhaling mold spores can be damaging to your health, and special equipment and protective gear may need to be used to safely remove an infestation without causing it to spread to other parts of the house.

Removing Mold From Air Conditioner Ducts

If you are going to go about cleaning the mold from your ductwork on your own, your choice of cleaning solution will be critical to your success. After all, what you decide to use and how you decide to clean the HVAC system can either contribute to enhanced growth or remove the unwanted infestation completely. You can concoct a cleaning solution made from common household items:

  • One tablespoon of household detergent
  • One-half tablespoon of baking soda
  • One cup of water

When working with non-porous surfaces, you can also use one-part bleach to 16-parts water. There are commercial-grade solutions as well that have been approved for mold removal by the EPA.

Whether you use these products or your household solution, you need to have the right protective equipment on. Have a pair of thick industrial-grade plastic or work gloves, wear a pair of coveralls or a splash apron, and have safety goggles. Because of the respiratory and other health conditions causes by inhaling mold spores and the cleaning products being used, you should also wear an N-95 mask when cleaning the ductwork or working around mold. Always make sure to remove gear before leaving the infected area and entering other parts of the home.

removing mold from air conditioning ducts

To remove the mold, begin by turning off your HVAC system. You can turn it off at the breaker to be sure no one tries to turn it on while you are working. If you know the source of the mold and can reach the area, isolate the portion of ductwork with bladders to keep mold spores from escaping. Scrub the area with a light brush or wet rag to loosen the fungi. Continue scrubbing and washing until you make progress with cleaning off the visible infestation. You will then need to wipe down the area with a clean damp cloth to remove leftover residue. Make sure you thoroughly clean the evaporating coils as well.

You can use a wet vacuum to absorb any leftover standing water in the ductwork, as letting water remain sitting around will just create a new opportunity for mold to grow. You can use a fan area to increase airflow to dry out the system before turning the unit back on. Any rags or sponges used in the process should be disposed of in heavy-duty airtight trash bags and taken straight out to the dumpster or waste receptacle.

Preventing Mold Growth in Ductwork

Now that you’ve cleaned off the active growth, you need to take action in preventing new colonies of mold. After cleaning, you can use an EPA registered disinfectant fogger to kill spores that may have escaped. You can also apply a mildew inhibitor to your entire HVAC system. Be sure to select a product that is specifically formatted for heating and cooling units and is registered with the EPA. This will limit the risk of applying an ineffective and toxic chemical solution to your unit and the air inside your home. If you don’t take steps to prevent growth, you can have another mold problem within just a few weeks in the same area.

Professional Mold Remediation 

The best way to ensure mold remediation is to call in experts. MoldRemedian.io connects you with the qualified and certified mold remediation companies in your local area. 

window mold removal experts

Mold removal companies rely on equipment to help isolate locations of growth. You may find a tear or hole in the ductwork under the house creating excessive moisture in the air, and, unless you are capable of handling the repairs, you will want to call an HVAC company to do the work. Doing the job right can reduce the risk of having to deal with the same situation later on. You are also investing in your family’s health and safety, which is never worth the risk.

Keeping an Eye Out For Mold

The smallest colony of mold can lead to a re-infestation, and it could move outside the ductwork and into another area of your home. Wherever you find water accumulation and humidity, you are looking at a place that can easily become compromised. Unless you stop the source of moisture by sealing off leaks, making repairs, or running a dehumidifier, you may be looking at scrubbing new vents, flooring, walls, or ducts in the future. To rid your life of a mold problem, contact the team at Mold Remediation We have years of experience and deep knowledge of mold growth and removal to make sure your home is safe and free of harmful mold spores.

black mold in air conditioner

Mold Inspections

Hiring a professional mold inspector will give you peace of mind. Being in a position where you are uncertain as to the toxicity of mold in your residence can be extremely stressful.

At moldremediation.io, we pride ourselves on being quick, thorough and effective in how we communicate the mold remediation tests that we perform for our homeowner clients.

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