If you’re shopping for air filters with the goal of improving your home’s air quality and protection for your furnace and/or air conditioner, you’ll want to know how to understand Minimum Efficiency Reporting Value (MERV) ratings. MERV is simple to understand: It’s essentially a system that shows an air filter’s capacity to trap particles of varying sizes, with the higher numbers trapping smaller particles. Here’s how it works:
- Standard air filters are generally rated MERV 1 to 4, and they offer little by way of improving air quality. Manufacturers, however, use them because they keep HVAC systems free of large particle buildup, while allowing proper airflow through the system. If you’ve never changed the type of filter your equipment came with, it likely contains this standard filter.
- MERV 5 to 13 air filters can remove even smaller particles without greatly compromising airflow. In fact, the Environmental Protection Agency (EPA) reports that air filters rated between MERV 7 and 13, when changed regularly, perform almost as effectively as highly touted High Efficiency Particulate Air (HEPA) filtration systems. In addition, these filters offer quieter operation, better airflow and cost less than HEPA filters.
- The highest-rated MERV filters, 14 to 16, are usually not used in residential applications. They restrict airflow too significantly due to their very dense, tight filter fibers that trap very small particles. These are usually reserved for hospitals or other settings where extremely clean air is necessary.
The best course of action to take when upgrading air filters involves consulting your HVAC contractor, or reading the heating and cooling equipment’s manual. The end goal should be to achieve better air quality with a filter that traps smaller particles than your existing, standard filter, while assuring that the proper amount of air can move through the filter. This is air your furnace and A/C depend upon for proper, efficient operation, and a long-lasting service life.
Use the right furnace and air conditioner filters to protect your HVAC system from dirt buildup and to improve indoor air quality. For more information about air filters, contact Mowery Heating, Cooling and Plumbing today. We’ve served homeowners in greater Indianapolis since 1970 with quality HVAC services.
Our goal is to help educate our customers in Brownsburg, Indiana and surrounding areas about energy and home comfort issues (specific to HVAC systems).
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