Updated: 9/1/2025
Discovering mold in your home can be concerning. Beyond the unsightly appearance and musty odor, mold can trigger allergies and pose health risks. Many homeowners turn to air purifiers as a potential solution. But how effective are they against mold? As indoor air quality specialists in the St. Louis, MO area, we’ll break down how air purifiers can help with mold, explore the best types for the job, and address some common misconceptions.
Signs You Have Mold in Your Home
If you suspect you have a mold problem in your home, search high and low to find it. There are a few common signs of mold growth in your home.
- Your home has a musty smell.
- Your home tends to be dark and may harbor moisture.
- You’ve noticed splotchy marks on walls, trim, and other surfaces of your home; that surface may warp, peel, or crack.
- Bleach lightens the splotchy marks, or removes them.
- The splotches continue to grow and expand.
- You or your family are experiencing runny or stuffy noses, a dry cough, or red eyes.
Can Air Purifiers Help with Mold?
Yes, air purifiers can help with mold, but it’s crucial to understand their limitations. Air purifiers work by filtering airborne particles, and mold spores are indeed airborne. A good air purifier can capture these spores, reducing their concentration in your indoor air. This can lead to several benefits:
- Reduced Airborne Mold Spores: By trapping spores, air purifiers can help prevent them from landing on new surfaces and potentially starting new mold colonies.
- Improved Air Quality: Removing mold spores, along with other allergens and pollutants, can lead to cleaner and healthier air.
- Odor Reduction: Some air purifiers with activated carbon filters can help reduce the musty odor associated with mold growth.
- Allergy Symptom Relief: For individuals sensitive to mold, reducing airborne spores can help alleviate allergy symptoms like sneezing, coughing, and itchy eyes.
However, it’s essential to recognize that an air purifier is not a standalone solution for mold. It addresses the symptoms (airborne spores) but not the source of the problem.
Will an Air Purifier Get Rid of Mold?
No, an air purifier will not get rid of existing mold growth. Air purifiers are designed to clean the air, not to eliminate mold colonies that are actively growing on surfaces like walls, ceilings, floors, or furniture. These mold colonies need to be physically removed and the underlying moisture issue that caused the mold growth must be addressed.
Think of an air purifier as a helpful tool in managing mold issues, similar to how a vacuum cleaner helps manage dust. It can remove airborne particles, but it won’t eliminate the dust that has already settled on surfaces.
To truly get rid of mold, you need to:
- Identify and Eliminate the Moisture Source: Mold thrives in damp environments. Leaky pipes, high humidity, condensation, and poor ventilation are common culprits. Addressing the moisture problem is the most critical step.
- Physically Remove the Mold: Mold growing on surfaces should be cleaned and removed. For small areas (less than 10 square feet), you can often do this yourself with appropriate safety precautions (gloves, mask, eye protection) and a mold-killing solution. For larger infestations, professional mold remediation is recommended.
Once the mold is removed and the moisture issue is resolved, an air purifier can then play a valuable role in capturing any remaining airborne spores and helping to prevent future issues.
What is the Best Air Purifier for Mold and Dust?
When choosing an air purifier to help with mold and dust, look for specific features:
- HEPA Filter: High-Efficiency Particulate Air (HEPA) filters are essential for capturing tiny airborne particles like mold spores and dust. They are designed to remove at least 99.97% of particles 0.3 microns in diameter. Make sure the air purifier you choose uses a true HEPA filter, not a “HEPA-like” or “HEPA-type” filter, which may be less effective.
- Activated Carbon Filter: While not directly targeting mold spores, activated carbon filters are excellent at adsorbing gases, odors, and volatile organic compounds (VOCs), including the musty smell associated with mold. A combination of HEPA and activated carbon filtration is ideal.
- Appropriate CADR Rating: The Clean Air Delivery Rate (CADR) indicates how quickly the air purifier can clean a room of a specific size. Choose an air purifier with a CADR rating suitable for the size of the room where you intend to use it.
- Ozone-Free: Avoid air purifiers that produce ozone, as ozone is a lung irritant and can be harmful, even at low levels. True HEPA filters clean the air without producing ozone.
There isn’t one single “best” air purifier for everyone, as the ideal choice depends on your specific needs and the size of your space. However, brands known for producing effective air purifiers with HEPA and activated carbon filters include (but are not limited to):
- Coway
- Levoit
- Blueair
- Dyson (some models)
- Rabbit Air
- Alen
Is a Dehumidifier or Air Purifier Better for Mold?
A dehumidifier is generally more crucial than an air purifier for preventing and managing mold growth. Mold thrives in environments with high humidity levels (typically above 60%). A dehumidifier works to reduce excess moisture in the air, making it less hospitable for mold to grow.
Here’s a breakdown:
- Dehumidifier: Addresses the root cause by controlling humidity levels and preventing mold growth.
- Air Purifier: Addresses the symptom by removing airborne mold spores and improving air quality.
Ideally, you should use both in areas prone to mold growth or where mold has been an issue.
- Use a dehumidifier to maintain a humidity level between 30% and 50%.
- Use an air purifier with a HEPA filter to capture airborne mold spores and improve air quality.
If you have to choose one, a dehumidifier is often the more proactive step in preventing mold from flourishing. However, if you’ve already addressed the moisture issue and removed the mold, an air purifier can be very beneficial in cleaning the air of residual spores.
Can Air Purifiers Cause Mold?
No, air purifiers themselves do not cause mold growth. In fact, they are designed to help remove mold spores from the air. However, a dirty air purifier filter can potentially become a breeding ground for mold if it traps moisture and organic matter.
To prevent this:
- Change Filters Regularly: Follow the manufacturer’s recommendations for filter replacement. Dirty filters reduce the air purifier’s effectiveness and can become sources of pollutants.
- Ensure Proper Ventilation: Air purifiers work best in conjunction with good ventilation. Address any underlying moisture issues in your home.
By maintaining your air purifier and addressing the root causes of mold growth, you can ensure your air purifier remains a helpful tool in creating a cleaner and healthier indoor environment.
How Whole-Home Purifiers Integrate with Your St. Louis Air Conditioning and Heating System
Meyer Heating and Air recommend Sanuvox air purification systems. The Sanuvair S300 uses HEPA filtration, UV air purification, and odor reduction, and ties directly into the ductwork of your home’s forced-air HVAC system, or via its own piping.
Our technician will examine your ducts and existing heating and cooling system to determine the best way to install this Sanuvox air-cleaning rockstar, and will provide a detailed estimate for the cost of the unit, plus parts and labor for the installation process.
If you’re dealing with persistent mold problems or have questions about improving your home’s air quality, our team at Meyer Heating & Air has the expertise to help. We offer comprehensive indoor air quality assessments, professional recommendations on air purification and dehumidification systems, and solutions to address the root cause of moisture issues. Don’t let mold compromise your family’s health and comfort. Contact us today for reliable service in the St. Louis, MO area.