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How to prevent mold from growing in your HVAC system

Areas in the house that aren’t easily seen are always the hardest to keep clean. Not just because they’re usually difficult to reach, but by not looking at them regularly, it’s easy to forget that they should be cleaned in the first place. This usually just means being extra diligent during spring cleaning season to think of the areas that tend to be left out and are in need of a deep clean, but there are other areas in the house — namely, within the vents and ducts that connect to the furnace and A/C — that will require extra work. Because letting these spots go their own way can lead to the development of mold and mildew within the ducts, and that poses a serious health risk to everyone within the house. So besides unscrewing all the vents and trying to reach deep into the ducts with a broom, what are the best ways for homeowners to prevent mold growth in their home’s HVAC system?

Remember to Change the Filters

Furnace filters need to be regularly checked and changed every 30–90 days. This helps prevent air pollutants and contaminants that typically get caught by the filter from slipping through and making their way into the ducts or out into the home — including mold spores. If the furnace filter becomes too clogged, and mold spores either become detached from the dirty filter, or slip through, they can become lodged in the ducts and begin to grow into a full mold outbreak. And once that spread has occurred, homeowners will need to take more serious measures to eradicate the outbreak.

Install Air Purifiers and UV Light Cleaners

To fight off mold spores before they reach the furnace filter, homeowners should consider adding an in-home air purifier or UV light air cleaners. Stand-alone air purifiers help filter additional particles out of the air and boost air quality in a single room, but for homeowners concerned with their entire system, there are more advanced setups that are installed directly into a home’s HVAC system, providing air purification to the entire home. 

These systems can then be supercharged when combined with a UV light attachment for the home’s HVAC — an additional device that sanitizes the air by killing off contaminants like mold spores through UV exposure. UV light attachments are relatively new additions for home HVAC systems, which means they are still fairly expensive to install. However, combined with an air purifier, these devices drastically reduce the presence of mold, mildew, pollen, dander, and other contaminants, increasing indoor air quality.

Avoid and Reduce Humidity

Damp air is the ideal environment for mold to cling onto and spread. Collected moisture and condensation in dark, warm areas — such as in the corners or sides of ducts — also provide the perfect spot for mold to move in and grow. So to prevent the possibility of mold gaining a foothold to spread out within the home’s HVAC and furnace, homeowners should find ways to cut down on their indoor humidity levels. One helpful activity is opening up the doors and windows when possible to increase airflow throughout the home, and equalizing the indoor environment with the outdoor. However, this is not always a viable solution — especially in winter. Which is why homeowners should also consider installing a whole home dehumidifier.

Attached to the home’s HVAC unit, similar to the air purification system setup, the integrated dehumidifier allows homeowners to more precisely control their in-home humidity, preventing moist environments where mold loves to thrive from forming inside the ducts.  

Mold is never a welcome guest for homeowners. Doing everything possible to keep it out of a home will help homeowners ensure the safety and quality of their indoor air. If you are worried that mold may have found a way into your home, or are worried about the cleanliness of your home’s ductwork, schedule an annual HVAC inspection with the team at Duane Blanton Plumbing, Sewer, Heating, and Cooling. With over 30+ years of hands-on experience, the team at Duane Blanton will be able to diagnose any HVAC issues, make minor repairs on the spot, and recommend additional ways to keep homeowner’s HVAC systems running without issue all year long. Reach out to the professionals at Duane Blanton to schedule your home’s HVAC inspection today, via phone at (815) 781-2567, or schedule online right from the convenience of your browser!

Duane Blanton Plumbing, Sewer, Heating, and Cooling is proud to be a Bryant Factory Authorized Dealer, offering top-quality heating and cooling options to fit the specific needs of Duane Blanton customers. The quality, comfort, and efficiency of Bryant Heating & Cooling Systems’ products naturally aligns with Duane Blanton’s drive to provide an exceptional customer service experience. Ask a Duane Blanton Plumbing, Sewer, Heating, and Cooling expert today about the advantages of upgrading to a new Bryant Heating & Cooling system for your home!


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