AC Filters: What Are MERV Numbers and What do They Mean for Your Hattiesburg MS Home?

Published on: June 22, 2012

“MERV” is an acronym for Minimum Efficiency Rating Value. The MERV rating is a number that is assigned to air conditioning filters that indicates the filter’s efficiency at capturing micron sized particles when air is passed through the filter. The higher the MERV rating, the better the overall performance of the AC filter. For residents of Hattiesburg, MS, a higher MERV rating is recommended to ensure top performance of the AC unit, and to make sure that the performance of your unit remains optimal.


The MERV rating indicates how efficient the air conditioning filter is at removing dust and particles from the air as the air passes through the filter. The more efficient the air filter, the fewer AC maintenance service calls will be required. If the AC filter is not efficient when it comes to removing particles from the air, the particles are drawn into the HVAC unit, which requires more frequent air conditioner maintenance calls. Another benefit of a good quality filter is that the ductwork will remain clean and air circulation throughout the home will be more efficient and effective.


MERV ratings range from 1 to 16. Measurements for MERV ratings are calculated in microns. Microns are small particles and may consist of dust, smog, dirt, pet dander, viruses, insecticides, wood particles, tobacco and other smoke, spores, pollen and bacteria. MERV ratings for residential home AC filters usually range from 1 to 4. For commercial buildings, MERV ratings for filters will usually range between 5 and 8.


Residential AC filters are not very effective at removing particles from the air. These filters are usually disposable and do not catch particles smaller than 10 microns. AC filters for commercial HVAC systems are generally more effective at removing particles from the air. Many commercial grade AC filters remove particles as small as 3 microns from the air. However, discriminating homeowners may purchase AC filters with a MERV rating between 5 and 8 for better air cleaning ability. Though these filters cost a bit more, they will keep the indoor air quality much healthier, as the filter will trap smaller particles and keep them from traversing through the HVAC system.


Industrial buildings will often utilize AC filters with a MERV rating somewhere between 13 and 16. These AC filters will trap particles as small as 1 to 3 microns. For the best air quality possible, homeowners may choose to purchase these commercial grade filters, at a cost substantially higher than the standard residential AC filter. For homes in Hattiesburg MS, where dust and environmental contaminants are prevalent, purchasing AC filters with a MERV rating between 13 and 16 is an excellent choice, particularly if anyone living in the home experiences respiratory issues or allergy problems.


Residential AC filters with low MERV ratings of between 1 and 4 include:

* Permanent Metal Filters
* Disposable Panel Filters
* Fiberglass and Foam Filters
* Hogs hair
* Automatic Rolls

Residential and commercial grade AC filters with MERV ratings between 5 and 7 include:

* Pleated Panel Filters
* Ring Panel Filters
* Synthetic Media Filters
* Cube Filters
* Self Supported Filters

AC filters with MERV ratings 8 and above include:

* Extended Surface Pocket Filters
* Certain Pleated Panel Filters
* Rigid Cell Filters
* Pleated Nordic Pure Filters
* HEPA Pure Pleated Filters


During your annual air conditioner maintenance, your AC service professional will be able to assess the effectiveness of the filter type you are using. If the MERV rating is not high enough, your AC service professional will advise you with regards to the type of filter that will be more effective for your system.


If you have questions about the best AC filter for your HVAC system, ask your AC service professional during your next maintenance session. The technician will provide you with information about the type of filter to purchase, as well as the optimal MERV rating for your needs. For those with allergies, asthma and respiratory problems, a higher MERV rating may be desired.