In short: no! When you’re staring at rows upon rows of filters at the hardware store, they certainly seem to blend together. But there are several key differences between HVAC filters that you should pay attention to when shopping.
The Action Air team has composed this guide to help you discern what air filter you need. Read on to find out more!
MERV Filter Ratings
Before deciding which filter is right for your family, it is necessary to understand how they are rated – the MERV system. MERV stands for Minimum Efficiency Reporting Value. Every filter on the market today has a MERV rating that reflects its capacity to trap airborne particles. The MERV scale ranges from 1-20, the highest performing filters have a rating of 20.
At the low end of the scale, filters trap large particles like dust, dust mites, spray paint, and pollen. In the middle range, hair spray, auto emissions, and micro-droplets from sneezes are caught in the filter. The best filters, with ratings of 15 and above, trap all bacteria, viruses, and all combustion smoke.
However, just because a filter has a high MERV rating does not mean it is the best match for your HVAC system. High MERV filters can impede the flow of air through your HVAC system, hiking up your energy bills as a result.
Different Varieties of Filters
1. Spun Fiberglass Filters
Spun fiberglass filters are the cheapest filters on the market and are designed to simply protect your HVAC system. They have a low MERV rating, typically between 1 and 4. Fiberglass filters block large particles from interfering with your air conditioning system.
2. Electrostatic Filters
Electrostatic filters use small cotton and paper fibers to generate static charge and trap particles. In general, electrostatic filters have high performance levels, boasting MERV ratings of up to 15. They come in washable and disposable varieties. If allergen removal is a concern for your family, electrostatic filters are an excellent choice.
3. Disposable Pleated Paper of Polyester Filters
Pleated filters are advantageous over flat filters due to increased surface area. With pleats, there is more area on a filter to remove particulates and pollutants from the air. Therefore, in general, pleated filters receive higher MERV ratings than their flat counterparts.
4. Disposable Pleated High MERV Filters
Disposable Pleated High MERV Filters have a MERV of 5-8 and filter 80-95% of particles 5 microns or larger. They are about four times more expensive as a fiberglass filter but are much more effective.
5. HEPA Filters
High-Efficiency Particulate Air (HEPA) Filters capture 99.97% of particles .3 micrometers or larger in size. In other words, they are really good at filtering the air. HEPA filters have a MERV rating of 13 or more and trap bacteria, viruses, and smoke.
Despite their high-performance rating, HEPA filters are not the best choice for most homeowners. Most residential HVAC systems aren’t powerful enough to push air through dense HEPA filters.
Are all filters the same? No, but they all need installation!
We hope this guide is helpful as you select a filter for you home. If you need help with the next steps: installation, HVAC maintenance, and repair, the Action Air team is here for you! We are a locally owned and operated HVAC company that has served the Indianapolis area since 1986. To schedule service, call us at 317-585-8981, or check out our website.