How MERV Ratings Work
Are you having problems with your air quality? Are you looking to improve your air filtration? Then you’ve probably come across a very important term – MERV ratings. So, what is a MERV Rating?
MERV – Air Quality, Efficiency, and So Much More
MERV, or the Minimum Efficiency Reporting Value, tells you how effective your air filter is on a scale from one to 16.
The higher the MERV rating on a filter, the fewer airborne particles and other contaminants floating through the air can pass through it.
There are two different factors that play into the MERV rating: (1) The ability to remove large particles that are between 1-10 microns that may include pet dander, pollen, dust mites, debris, etc; and (2) The filter’s ability to remove submicron particles that are smaller than 1 micron.
If you’re not sure how small a micron is (we don’t blame you), take a look at this chart to get an idea of what gets through at each MERV Rating level.
The MERV Rating Scale
Here’s how Air Filter MERV Ratings work:
- MERV 1 to 4: less than 20% of large particles (3 to 10 microns) are picked up
- 5 to 7: 20-69% of large particles are picked up
- 8 to 10: Approximately 85% of large particles and 50% of small particles (1.0 to 3.0 microns) are picked up
- 11 to 16: Over 90% of large particles and 70-90% of small particles are picked up
- 17 to 20: Even the smallest of particles (< 0.3 microns) are picked up
What MERV Rating Should I Choose?
As we previously mentioned, filters are tested for pollen, textile and carpet fibers, mold spores, dust, pet hair, bacteria and tobacco smoke. Most residential systems can adequately remove these contaminants with a filter rated MERV 7-12. Higher ratings (13-16) are typically found in hospitals and settings where exposure to bacteria can be particularly harmful.
You want to keep two main factors to consider when considering what kind of filter you use while keeping your budget in mind. (The wrong MERV rating and filter can actually damage your system too!)
1. Filters Need to Match Your Environmental Needs
Every home or office is different. For example, a dog owner is going to have more air quality concerns than a home without a furry friend. You should ask your trusted HVAC specialist what kind of filter will take care of your specific needs.
We would be more than happy to help!
2. Filters Will Affect Your HVAC Efficiency
When considering what MERV rating you will use, it’s important to note that your system’s efficiency is greatly impacted by your filtration. The more your filter catches, the faster it gets clogged. This results in either more frequent replacements or lower efficiency, both costing you money.
A Higher MERV Rating Can Damage Your System
When some people upgrade their MERV rating, they keep their standard 1″ filter, but this can actually damage your system. Here’s how:
- Because your filter is now catching more particles, it will fill up faster.
- Because it fills up faster, you need to replace your filter more frequently.
- If you don’t replace your filter more frequently, your system will need to work harder to push air through the clogged filter.
- Your motor will overwork and get burned out far more quickly, costing you anywhere from $300-$800.
If you’re going to get a higher MERV rating, ask about if you need a thicker filter. With your standard filter, the 1″ pleats will fill up more quickly than a thicker filter with 4-5″ pleats. The thicker the filter, the more filter material there is to fill up.
A great example is the Trane Perfect Fit Media Filter as seen below.
While 1″ filters are relatively cheap, they are replaced more often and result in lower system efficiency than something like the Trane Perfect Fit filter. It features around 30 feet of total filtration material (compared to the 1.5 feet in a standard 1” filter) that’s a higher quality. This allows it to provide maximum air quality without sacrificing efficiency.
Better yet, Trane recommends you only have to replace this filter once every six months!
If you need a higher MERV Rating on your filter, reach out to us, and we will help you find the perfect fit for your air filtration needs and budget.