When it comes to air filters, it's easy to assume that a higher MERV rating means better filtration. However, the best MERV rating for your HVAC system will depend on your needs and the efficiency of your unit. The Minimum Efficiency Reporting Value (MERV) is a scale that measures how well an air filter can prevent dust and other contaminants from entering the air stream. The ratings range from 1 to 16, with higher ratings trapping small particles more effectively than lower ratings.
Unfortunately, MERV ratings of 1 to 4 are not recommended for homes as they provide insufficient filtration. These filters must be replaced and cleaned more often than others. It's also important to select the right MERV rating, as an incorrect one could damage your HVAC system. Contrary to popular belief, a higher MERV rating isn't always the best choice for homes.
According to the U. S. Environmental Protection Agency, a MERV rating of 5 to 8 can capture and remove particles that could be harmful to health. Some experts recommend a MERV rating of 9 to 12 for air conditioning systems, as it can reduce the spread of COVID-19 particles.
Generally, filters with a MERV rating of 16 or lower are suitable for residential, commercial and general hospital use. MERV ratings are determined through tests conducted by the American Society of Heating, Refrigerating and Air Conditioning Engineers. If you don't have pets or suffer from severe allergies, a MERV rating of 5 to 8 may be suitable. This rating effectively captures pollen and other particles ranging in size from 3.0 to 10.0 microns.
On the other hand, filters with a MERV rating of 17 to 20 are bulkier as they are designed for high-strength filtration in manufacturing buildings. The MERV rating scale also includes percentages based on the likelihood that an air filter will trap air contaminants in terms of particle size. A MERV rating of 9 to 12 is sufficient to capture particles smaller than 1 and no more than 3 microns. Residential systems will not accept filters with a MERV index greater than 12, unless it has been previously adapted to a higher-efficiency filter.
In conclusion, selecting the right MERV rating for your HVAC system is essential for efficient operation and optimal air quality. You can check your HVAC system's owner's manual to determine the appropriate MERV rating for your system.
