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All Filters Are Not Created Equal

Clogged or dirty air filters can cause your heating and cooling system to operate improperly, leading to possible system damage and/or replacement. Air filters can also help enhance indoor air quality (IAQ), which is a key component to good health. So, performing regular air filter maintenance is crucial to keeping your system running smoothly.
The good news is, when it comes to simple or do-it-yourself HVAC maintenance, it doesn’t get any easier than air filter maintenance. Air filters should be cleaned or replaced regularly. Also, a good way to test if your air filter is efficient at removing pollutants, allergens and other particles from your home is to perform this test. Place your current air filter horizontally, then pour common table salt though the filter. If some or all of the salt passes through and come out the other side, this is a sign that your filter will not slow down dust particles or pollutants of similar size. It may be time for a new filter or a more efficient one.
So, what types of filters are best at enhancing IAQ? The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) has a rating system called the minimum efficiency reporting value (MERV). MERV ratings range from 1 (lowest) to 20 (highest), and is based on the following: the ability of the air filter to remove particles and resist airflow and the filter’s projected life expectancy.
Here are the three main types of air filters and their MERV ratings:

  • Flat-panel fiberglass. These filters are composed of layers of fiberglass fibers, are disposable and usually carry a rating of 1 to 4. These inexpensive filters have a medium efficiency rating for collecting larger airborne particles and a lower rating for capturing smaller dust, dander and bacteria particles.
  • Pleated polyester. These filters have a rating of 5 to 13; the pleats allow for more surface area to capture smaller air particles and pollutants.
  • High-efficiency particulate air (HEPA). Recognized by the Occupational Safety and Health Administration as the top filter for removing air particles and pollutants. HEPA filters have a rating of 17 to 20, but there is one drawback- their size. Most residential heating and cooling systems are not built to accommodate HEPA filters; switching to one will likely require an HVAC professional to retrofit your furnace.

In the meantime, it is always a good idea to change your old filter. Refer to your furnace manual to find out the proper size, open the filter compartment or locate the filter slot, slide out the old one and properly dispose of it. Determine the airflow direction and install the new filter.
For more air filter efficiency information or for a fall tune-up, Call Dixie today and it’s done.