microparticle performance rating (MPR)

What Do Those Air Filter Ratings Other Than MERV Mean?

What Do Those Air Filter Ratings Other Than MERV Mean?

The heating/cooling (HVAC) system in your Tulsa-area home requires relatively little maintenance, but this maintenance needs to be provided on a regular basis. Besides annual check-ups from a qualified HVAC technician, the most important aspect of an efficiently running heating/cooling system is the proper selection and regular replacement of your equipments' air filters. Choosing appropriate filters according to universally accepted air filter ratings such as MERV is where you should start.

Air filters generally carry MERV ratings, a widely accepted rating system developed by ASHRE, the American Society of Heating, Refrigerating and Air Conditioning Engineers. The acronym MERV stands for Minimum Efficiency Reporting Value. The rating numbers, which extend from 1-16 for residential air filters, apply to the particle size a specific filter is capable of trapping. MERV 1-4 filters can capture particles that are 10 microns or larger in size. Filters rated between 5-13 capture increasingly smaller particulate down to as tiny as 1.0 micron. Most experts recommend homeowners use air filters with ratings of from MERV 8-12 for the best balance of economy and efficiency. Anything higher than a MERV-12 will certainly be more aggressive in its filtering capabilities but may also restrict airflow to a point that could be harmful to your equipment.

Some air filter sales outlets have started using alternative air filter ratings other than MERV. These are not approved by ASHRE and may cause some confusion when you're trying to compare efficiency and cost of different filters. Home Depot is one example of a company that's switched from MERV to something called FPR, which stands for Air Filter Performance Rating. An FPR-8, however, is not equal to a MERV-8. MPR, or Microparticle Performance Rating, is another arbitrary rating system used by a certain filter manufacturer. Neither FPR nor MPR are recognized by ASHRE, whose MERV system has been universally recognized and used for decades.

As the largest full-service HVAC equipment and service provider in the Tulsa area, Air Assurance has been providing excellence to our clients since 1985. Contact us for more info or advice on air filter ratings or any indoor air topics.

Our goal is to help educate our customers in the Tulsa and Broken Arrow, Oklahoma area about energy and home comfort issues (specific to HVAC systems). 

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