Regular replacement of your HVAC filter is important, but do you know what you’re looking for before going air filter shopping? Understanding the differences between filter types and their minimum efficiency reporting value (MERV) ratings will help you make an informed decision regarding which HVAC filter is most appropriate for your home’s cooling and heating system.
Most HVAC air filters will have a MERV rating between 1 and 16 (ratings from 17-20 are reserved for high-efficiency particulate air (HEPA) filters not used in typical forced-air HVAC systems). As a general rule, filters with MERV ratings between 1 and 4 are only designed to protect your HVAC equipment and will not improve indoor air qualtiy (IAQ). Once the rating reaches 13, most airborne particulates in your home can be captured on your air filter, significantly improving indoor air quality. MERV ratings of 14-16 indicate that a filter will remove up to 85 percent of the airborne contaminants in your home.
In addition to the MERV rating, before going air filter shopping, you should be aware of the different types of filters available:
- Fiberglass air filters are flat panels having MERV ratings between 1 and 4. Although inexpensive, they do little to improve air quality. They will provide minimal protection for your HVAC equipment.
- Polyester and pleated air filters can trap a larger percentage of airborne particles. These typically have a MERV rating between 8 and 13 and offer a good balance between maintaining air quality and allowing for adequate system airflow in the home.
- Washable air filters with MERV ratings between 1 and 4 are generally not recommended due to their tendency to collect fungus and bacteria that will continuously circulate inside your home.
- High-efficiency air filters with MERV ratings between 14 and 16 are made from pleated filter paper or synthetic polyester fibers. Although they do trap the majority of airborne pollutants, they may impede the airflow within your HVAC system. They generally are restricted for us in homes with special air quality concerns, and likely will require serious system modifications to work with your equipment.
IIf would like additional advice before your next air filter shopping trip, contact the friendly staff at Hansberger Refrigeration & Electric Co. We have been serving the Yuma area since 1952.
Our goal is to help educate our customers in Yuma, Arizona about energy and home comfort issues (specific to HVAC systems). For more information about air filters and other HVAC topics, download our free Home Comfort Resource guide.
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