Changing your filter is integral to proper AC maintenance. To find the best AC filter, you should compare your needs with the abilities and price of the filter. Here are a few things to consider.
How to Compare Filters with MERV Ratings
Developed in 1987, minimum efficiency reporting value, or MERV, is a system for evaluating the quality of filters. It's a score, on a scale of 1 to 16, that rates the absolute minimum number of particles filtered. Scores with 16 remove 95 percent of irritants or more. Those with a score of one remove almost none. By using MERV ratings, you can effectively compare all brands of filters to know which one is the highest quality. However, choosing the best AC filter isn't just about MERV ratings; you also need to factor in the price.
Cost vs. Use of Air Filters
There's no use paying money for a filter that removes next to nothing. Likewise, you probably won't see much more benefit by purchasing a filter made of space-age material. Somewhere in between, you'll find the delicate balance between price and effectiveness. Also, the densest filters may strain out all particulates, but they will heavily strain your air conditioner, increase AC maintenance costs and raise your electric bill.
MERV Rating and Type of Particles Removed
The highest rated filters are used in hospitals and electronics manufacturing. They're also the most expensive. For practical purposes, most homes won't need to remove particles that small. The MERV rating on filters can be grouped to make it easier. Here are the typical aspects of each group:
- 0-3 - Residential filters aren't allowed to have ratings this low.
- 4 - This is the bare minimum residential filter. It's typical of window-unit ACs with wire-mesh filters.
- 5-8 - This group filters out the common household irritants like mold spores, pet dander, dust mites and even hair spray.
- 9-12 - This represents the superior level of home air filters. It can filter particles as small as lead, flour and automobile emissions. This is one of the best categories for balancing price and performance.
- 13-16 - This level is what hospitals use. It can filter out bacteria, sneezed droplets, smoke and even airborne makeup. For home applications, this level is most likely excessive.
- 17-20 - While not covered earlier, there is a higher rating for filters commonly used by the electronics manufacturing industry. In zero-contaminant wafer fabrication, these filters keep out almost everything. The cost is usually well beyond the means of most residential needs.
MERV vs. HEPA Ratings
HEPA filters are all the rage because of the ability to remove viruses and bacteria. However, HEPA filters are far too dense for most heating and cooling systems. In essence, they would simply plug the vent and not allow air to flow. That doesn't mean you can't have HEPA quality though. If you need the most superior air quality, then you can install a filter with a MERV rating of 12 or 13. It will remove bacteria. Then, you can add a separate air purifier with HEPA filtration to remove viruses and more.
Thermacon Service Company
Thermacon provides a full range of heating and cooling solutions to the Golden Triangle and SW Louisiana. If you'd like to learn more about our special Thermacon AC maintenance service that includes a 12-month supply of free filters, then call us today.