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Why MERV Matters When Choosing Air Filters

Air filters are a small component of your home’s overall heating and cooling systems; however, they have a big impact both on a system’s efficiency and a home’s comfort level.

Air filters are rated according to the Minimum Efficiency Reporting Value (MERV). The MERV rating shows how efficiently the air filter can trap particles; filters are rated from 1 to 16.

Particle measurements are established by “microns.” To give you an idea of how small some of the particles are, high-efficiency filters can trap particles that are 0.3 microns in size, which is smaller than the width of a human hair. Some of the types of particles air filters are designed to remove include pet dander, dust, pollen, spores and bacteria.

Air filters are rated in three categories for MERV:

  • Low-efficiency filters are rated MERV 1 to 4, and they trap particles beginning at 10 microns.
  • Mid-efficiency filters are rated MERV 5 to 12. They collect particles from 1 to 10 microns.
  • High-efficiency filters are rated MERV 13-16. Often, these types of filters are used in hospital settings, as they provide effective particle removal down to 0.3 microns, but the filters are fairly expensive.

Keep in mind that the filter’s surface and its efficiency are connected; you don’t have to necessarily purchase the highest efficiency air filter to get the best results. Experts suggest that medium-efficiency filters with pleated or extended designs, over time, have an increased lifespan. The material allows for a certain amount of dust to collect while maintaining adequate airflow and decreasing fan noise.

Airflow is critical, because if a system doesn’t get enough of it, the filter has to work harder to condition air, and this can lead to breakdown. It’s critical to consult your manufacturer’s guide for your HVAC systems to match the correct filter.

Which filter will work best for your system’s efficiency and the overall comfort of your home by giving you clean air? If you have questions, contact the experts at Arpi’s. We can help you select a filter so you can get better control over particles.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information, click here to download our free Home Comfort Resource guide.


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