When it comes to selecting the right MERV rating for your home and HVAC system, it is important to consult the owner's manual. This will provide you with the maximum MERV rating that is recommended for your system. Using a filter with a value higher than the recommended limit can have a negative impact on system efficiency and may lead to costly repairs in the future. MERV stands for Minimum Efficiency Reporting Value and is a standard measure of a filter's ability to remove particles from the air in your home.
The MERV rating scale ranges from 1 to 20, with lower grades indicating lower quality filters. To determine the MERV rating, 12 particles of different sizes, from 0.3 to 10 micrometers (µm) in diameter, are created in a laboratory environment. These particles are then divided into three different size ranges (E1, E2 and E3) and four sub-ranges that exist within each range. The first range, E1, includes particles with a size of 0.3 to 1.0 μm. E2 includes particles of a size of 1.0 to 3.0 μm, and E3 encompasses particles of a size of 3.0 to 10.0 μm.
The higher the MERV rating of a filter, the fewer dust particles and other contaminants can pass through it. A MERV rating of 1 may be effective for filtering particles from larger fibers but is generally not recommended in residential or commercial environments. Residential systems will not accept filters with a MERV index greater than 12, unless it has been previously adapted to a higher-efficiency filter. Many allergy sufferers and asthmatics rely on the MERV classification system to differentiate between ineffective and low-quality air filters from those that actually filter more impurities. It is best to follow the oven manufacturer's recommendations or consult an HVAC professional to determine exactly which MERV rating is best for your specific system. If your system is not capable of processing filters with higher MERV indexes, you may want to talk to your HVAC dealer about selecting a mid-range MERV filter, between 8 and 10. Filters with higher MERV ratings must be changed more frequently (at least every three months) to avoid airflow restriction that can cause the system to operate inefficiently or even damage it. By understanding which filters trap certain particle sizes, you can begin to get an idea of which MERV filter will work best in your home. A MERV filter with a rating of 16, for example, is designed for use in a more commercial environment.
Higher MERV ratings usually trap smaller particles, but as you'll see, it's not as simple as that. To ensure that you are selecting the perfect MERV rating for your home and HVAC system, it is important to consult an expert or read up on the topic before making any decisions. This will help you make an informed decision that will keep your home safe and comfortable.
