A Filter Acronym Guide: MERV, MPR, & FPR

Indoor air quality is a hot topic these days, for obvious reasons – but the truth of the matter is that air quality should always be top of mind if you want to live as healthy as possible in your central Maine home, especially during peak allergy seasons in the spring and fall.

If you own a forced air system (one with vents rather than baseboards or radiators), one of the most important keys to maintaining healthy air quality is to check your filters often – at least once a month during heating and cooling seasons – and to change disposable filters when they’re dirty.

Simply put, a clean filter will do a better job blocking the microorganisms, dander, and other tiny nasties that fly around inside your home; without those irritants in the air, your immune system will have more resources left to fight bigger battles. A clean air filter will also prevent your furnace or A/C from overworking, which means lower energy bills, less maintenance, and a longer lifespan for your equipment.

Choosing an HVAC filter

When it comes time to buy your replacement filter, you’ll encounter a sea of confusing acronyms. Don’t worry, they’re pretty easy to figure out once you understand a few HVAC filter basics.

Three common terms you might hear when shopping for a replacement filter for your HVAC system are MERV, MPR, FPR. Each term describes a filter system that uses a scale to define the size of the filter holes (higher numbers = finer filtration) – the only difference among the three systems is who manufactured them.

• MERV, or Minimum efficiency reporting value, is a measure developed by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE); MERV ratings range from 1-20.
• MPR, or Micro-Particle Performance Rating, pertains only to products developed by the 3M company; typical MPR ratings range from 300 to 2200.
• FPR, or Filter Performance Rating, is a filter rating system developed by Home Depot for the brands sold through its stores, including Honeywell; it uses a 1-10 rating scale.

How to convert MERV, MPR and FPR values

Here’s a conversion table of MERV, MPR and FPR ratings for common residential usage (higher-valued filters are often used in hospitals and operating rooms, but are not necessary for home use):

Need furnace maintenance in Androscoggin County, ME? Trust the pros at Murray-Heutz. Contact us today to schedule a visit from our heating experts.

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