Your air filter is one of the most important, yet forgotten, parts of your home’s air conditioning system. For people who have allergy issues, children with breathing problems or dogs that shed a lot, your home’s air filter can be the difference between good air quality inside your home and health problems.
That’s where MERV comes into play. MERV is the quality rating of an air filter. MERV stands for maximum efficiency reporting value. This scale is a way to measure how clean your air is designed by The American Society of Heating, Refrigerating and Air-Conditioning Engineers, or ASHRAE.
How does a MERV rating work?
The MERV scale ranges from 1-20. The lower range, 1-4, is the type of cheap, cardboard air filters you often see for sale at grocery stores. A decent MERV rating for an air filter is anywhere from 5 to 13, according to the United States Environmental Protection Agency. You can often find filters in this range at your local hardware store. One more thing – a MERV rating from 7 to 13 can be almost as efficient as a HEPA filter, which is the type of filters you commonly see at hospitals. (HEPA filters are not usually used in residential HVAC systems. But they have the highest MERV ratings, up to a purely efficient score of 20.)
Is a high MERV rating necessary?
This depends on your family’s needs. As mentioned above, if you have allergy or breathing issues, it is heavily encouraged that you make the investment in a high-quality air filter. A MERV rating of 5 is sufficient enough for HVAC fan operation and these rated air filters are cheaper than HEPA filters. In addition to investing in high-quality filters, you also need to change them regularly. Depending on your needs, this could be anywhere from every couple of weeks to every 1-2 months.