MERV ratings are a measure of the efficiency of air filters in capturing particles of certain sizes. The ratings range from 1 to 20, with 1 being the lowest level of filtration and 20 being the highest. For most residential applications, a MERV rating between 5 and 13 is recommended. A MERV 8 filter is a popular choice as it is quite a complete option and economical in price.
It is 90% efficient at trapping particles from 3 to 10 microns in size, including pollen, pet dander, lint, and dust mites. If you are concerned about outdoor air pollution, family members with respiratory problems, or pets in the house, then a higher MERV rating might be a good idea. MERV 11 air filters are the best choice for eliminating cigarette smoke, smog, and general allergens. They can also better eliminate odors from smokers or pets.
If you have allergies or live near smoke pollution, then a MERV 13 filter is the ideal choice. Using an air filter with a MERV rating that is too high can damage the compressor, heat exchanger, and air conditioner coil. Anything greater than a MERV 11 is designed for commercial or domestic households with family members suffering from respiratory problems. Choosing the right MERV rating is an important decision in terms of total cost, air quality, and product durability.
Follow manufacturer's recommendations for maintenance and replacement to ensure your filter is working properly.