When it comes to improving the air quality in your home, the Department of Health recommends using air filters that are capable of eliminating at least 99.97% of allergens and pollutants, including mold spores and dust particles as small as 0.3 microns. Generally, you should replace the filter every three to twelve months, depending on its size. For 1-inch thick filters, the usual recommendation is three months, while filters that are 4 inches or thicker usually last for twelve months. In the event of a wildfire, you may need to change your filter more often than usual.
To help you determine when it's time to replace it, there are certain indicators you can look out for. According to experts, filters with a high MERV content (from 1 to 16) tend to restrict air flow more than those with a low MERV content, which can be measured by the decrease in atmospheric pressure generated by the filters when they are installed. The easiest way to choose a replacement filter is to simply buy the same one you already have in your system. If your existing filters are perfect, make sure to note (or take a picture) of the size printed on the filter frame.
There are various types of air filters available, such as fiberglass, polyester, washable, pleated and electrostatic filters, each offering different air filtering capabilities. Any pleated HVAC filter can help improve your home's indoor air quality by trapping dust, pollen and other small particles. However, if you have furry pets or live in an area with high levels of air pollution (such as from wildfires), you may need to replace the filter more often. When air conditioning filters become clogged with debris and dirt, air cannot flow freely through the ducts, making your home less comfortable and potentially damaging the air conditioning equipment over time.
The Home Depot offers a full range of air filter accessories that can help keep your system running at peak performance. The air is charged with particles and passes through the filter only once before its results are measured. However, these are usually filters with a rating of at least MERV 11 – the classification in which filters begin to trap most particles the size of common allergens. To ensure that your home is properly protected from allergens and pollutants, it is important to choose an appropriate filter for your HVAC system.
The type of filter you choose will depend on your specific needs and budget. If you have allergies or asthma, it is recommended that you use a filter with a higher MERV rating for maximum protection against airborne particles.
