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Take These Steps to Stop Mold Growing on Your Air Conditioner Vents?

There are many reasons the vents in your home could be affected by mold growth. One common cause is attributed to the mixture of the cold vents and warm, humid air in the home. Take for example a situation where the temperature in the house is 76 degrees with relative humidity at 60 percent, and the air coming from the diffuser (vent) is 55-60 degrees. As the cold air passes, the exposed surface of the vent cools to 57 degrees. When the warm, humid air in the home comes into contact with the cold surface of the vent, condensation occurs. This contact of the warm air and the cold metal vent produces condensation. Subsequently, this leads to the formation of what is perceived to be mold. Often, the buildup observed on your vent is an accumulation of dust and other particles circulating in the air. When the particles become trapped on the surface of the wet vent, this will eventually lead to mold growth.

How To Prevent Mold Growth on AC Vents?

Preventing condensation, dust and particle accumulation on your vents is the simplest way to ensure you have good air quality inside your home. Below are some simple steps you can take to prevent mold from growing on youe air conditioning vents.

Ensuring your AC unit is serviced by a professional or as recommended by the manufacturer. A properly working air conditioning unit will circulate the air in your home and remove excess humidity that can lead to condensation and mold problems. Keep an eye out for any signs of AC problems. For instance, checking for any wet or condensation build up on the AC unit or on vents. Your AC unit isn’t cooling correctly. If the unit runs for short periods – this is called Short Cycling. Air conditioner short cycling is a condition where your air conditioner goes through its on-and-off cycles too frequently. When this happens, it’s impossible for your home to feel comfortable, drains your energy bill, causes high humidity levels, and causes mechanical problems. An AC system is complex and involves many systems, therefore, if you have any of these problems contact a service provider. Annual maintenance of all parts of your system, including the coils, can also help reduce the risk of mold spores entering the ducts.

Maintaining the proper humidity levels. Homes with high humidity levels (usually over 60% Relative Humidity) will in most cases have mold growing in bathrooms, the AC system, on fabrics, furniture, and other porous material if the conditions are just right. The ideal humidity levels in your home should fall somewhere between 30 and 55%. Lower humidity levels can cause excessive dryness and possible health concerns. In contrast, higher humidity levels can promote mold growth and can make your home hot, muggy, and uncomfortable. The simplest way to monitor your homes humidity levels is to purchase a humidity sensor. You can purchase one of these online for around $10. Some modern AC systems have these sensors already installed.

Changing your Air Conditioning Systems filters frequently. In most cases this should be done every 30 days or as indicated on the air filter packaging. Changing your air filter will provide adequate airflow for your unit and help to reduce the risk of mold growth. Also, you could consider investing in a high-efficiency particulate air filter (HEPA filter) these filters are designed to 99.9% of airborne particles like mold spores

Consider using a dehumidifier to control humidity levels in your home. Install a portable dehumidifier if you live high humidity locations or you have high humidity problems in your home. A dehumidifier can remove excess moisture from the air, which is needed for mold spores to thrive.

Maintain your home. Frequent cleaning using a vacuum with a HEPA filter and limiting the amount of dust in your house and can reduce mold spores.

Venting moisture is producing appliances. When cooking, taking a shower, using clothes dryers, and other items that introduce humidity into the home, ensure they are vented outside.

Install UV germicidal light in your ductwork. UV air purifiers work with your existing central HVAC system to help kill bacteria and other microorganisms in the air. These UV lights are installed inside the ductwork of your air conditioning system to sterilize microscopic particles, including mold spores that make it past the air filter.


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