Spring is in the air, and pollen is on its way if it hasn’t arrived already. Armed with the right air filter, however, you can substantially improve your indoor air quality. Deciding which air filter to choose is simplified by a rating called MERV (Minimum Efficiency Reporting Value) that grades the effectiveness of a filter’s ability to capture particulates.
Which MERV to choose?
MERV ratings range from 1-20, with a MERV of 20 being the best at capturing particulates. An air filter’s MERV rating is often found on the yellow EnergyGuide label. For residential use, you’ll see a rating anywhere from 1-16, as 17-20 ratings are for usually reserved for sensitive industrial and laboratory use. Filters rated 1-4 are the basic disposable filters. Filters in this range are primarily used to protect HVAC equipment, and are not intended to significantly improve indoor air quality.
Filters rated 5-7 show improvements capturing pollen, mold spores, dust mite body parts and droppings, and pet dander, but even after several passes through the filter, many contaminants remain in the air. The U.S. Environmental Protection Agency (EPA) recommends air filters rated MERV 8-13. Filters at the higher end (12-13) capture auto emissions and lead dust as well.
By design, air filters impede airflow in order to capture particulates. The higher the MERV rating, the more that airflow is impeded. This is why everyone shouldn’t just simply install a MERV filter rated 16. You should consult with your heating and cooling professional as to the best filter for your particular heating and cooling system. Filters in the 8-13 range are usually a win-win option for improving indoor-air quality and not hindering equipment performance. No matter what MERV air filter you buy, make sure you change it regularly. Nothing impedes airflow like a clogged filter.
How important are air filters?
The federal EPA reports that the air quality in the average home is five times more polluted than outdoor air, and 96 percent of homes have one or more serious indoor air quality problems. When you consider that more than 20 percent of people suffer from hay fever, those stats are something to sneeze about.
Contact Hovland’s, Inc. with any questions you have. We’re a family-owned and operated company providing HVAC services to west-central Wisconsin since 1922.
Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about air filters and other HVAC topics, download our free Home Comfort Resource guide.
|Air Filter image via Shutterstock|