Furnace and air conditioner filters exist to keep dust and other particles from clogging up the inner workings of your HVAC system, but they also serve another important role – filtering the air that circulates through your home so that you can breathe easier on a daily basis. But not all air filters are created equal: here’s what you need to know to choose a good one.
How Air Filters Work
Air filters work by passing air through a mat of close-packed fibers. The closer the fibers are packed together, the harder it is for particles to make it all the way through without being caught and removed from the airstream – but the harder it is for air to pass through, as well. That’s why furnaces an air conditioners come with maintenance instructions indicating what filters work with their specific models: a filter that’s too efficient will force the fan motor to work overtime just to circulate air.
But within the range of what your furnace or AC can handle, you should pay close attention to the filter’s Minimum Efficiency Reporting Value (MERV). Higher MERV ratings mean that a filter can filter out smaller particles, and filter larger ones more effectively.
For example, air filters with a MERV rating of 5-8 can remove the majority of the mold spores, pet dander and dust mites in the air circulating through your system. A high-efficiency filter with a MERV rating of 13-16, however, can catch sneeze droplets, fine particles such as facial powder, and most bacteria.
Because they offer increased resistance and clog faster as a result of smaller apertures and better ability to catch particles, higher-efficiency filters require more frequent replacement. With any standard filter, replacement is important and should be considered every month or two.
To learn more about taking control of your indoor air quality in the Charlotte, NC area, contact us at Ross & Witmer!