Question: Which AC Filter is right for my home and how often should I change it?

Answer: We get asked more about AC Filters than nearly any other AC System component. This is probably due to the fact that, aside from the thermostat, this is the AC System component that is managed the most by a homeowner or business owner.

In Part I, we detailed how a dirty or clogged filter can affect your AC System’s performance and your home’s air quality. We also gave you tips to inspect and maintain your AC System Filter. In Part II, we’ll help you understand the different types of Filter media and which Filter is right for your home.

There are several different categories of AC Filters and the differences are basically due to the Filter Media – the material used within the Filter catch pollutants. Some Filters are more expensive than others but they all accomplish the same mission.

Just like the efficiency of your AC System is calculated with a SEER Rating, an AC Filter’s efficiency is calculated by its MERV (Minimum Efficiency Reporting Value) rating. The lower the rating, the lower quality of the AC Filter. Here is a breakdown of the most commonly-found AC Filter types:

  • Fiberglass AC Filters:
    This Filter is very thin with a simple flat panel surface. This type of filter was originally designed for your air conditioning equipment, not to improve the quality of your air. This is the least expensive of the Filter types. However, you get what you pay for. This Filter’s MERV rating is only between 1 to 4. This is the lowest rating an AC filter can have. Only 10 percent of air pollutants are removed from the air, which may contaminate your AC System and ductwork if not replaced frequently.
  • Pleated AC Filters:
    This Filter can remove up to 45 percent of air pollutants in your home. It has a MERV rating of 10 to 13 and is more expensive than a Fiberglass Filter (in the neighborhood of $10 per Filter).
  • High-efficiency AC Filters:
    This is the most practical Filter for residential AC Systems and can remove up to 85 percent of pollutants. It has a MERV rating of 14 to 16, which is the second-highest rating tier. These Filters are a bit more expensive than Pleated Filters. These Filters are the most recommended by air conditioning technicians since they effectively remove most debris, dust and pollutants. High-efficiency Filters are recommended for families with allergies or respiratory ailments.
  • HEPA (High Efficiency Particulate Air) Filters:
    True HEPA filters can remove up to 98 percent of pollutants. It enjoys the highest MERV rating, which is 17 to 20. However, HEPA Filters can only be used with a whole house air filtration system or with a dedicated air purifier. HEPA Filters require a high amount of pressure to force air through the Filters, which is what leads to their high efficiency. A normal AC system could not support this type of filter as it is not powerful enough to penetrate the filter. Again, you get what you pay for. Your indoor air quality will improve dramatically with the use of a HEPA Filter.

When considering a High-efficiency or HEPA Filter type, keep in mind that these Filters may cause your AC System to work harder and/or run longer, which may shorten the life of your Air Handler’s components.

When shopping for a replacement AC Filter, BE SURE TO KNOW THE SIZE OF YOUR CURRENT FILTER. This is one of the most common mistakes homeowners make when buying replacement Filters. Buying the incorrect Filter will enable debris and pollutants to evade the Filter media – basically defeating the purpose of the Filter in the first place.

As we recommended in Part I, be sure to maintain your Filters and replace them regularly.

Your AC Today EMT can evaluate your home’s AC System and give you the best advice regarding the most suitable Filter type and the ideal replacement frequency. Proper Filter replacement combined with an AC Today Maintenance Agreement specifically tailored to your home is the best way to keep your AC System running at optimum performance.  Not only will a Maintenance Agreement save you money in the long run, it will help you avoid unwanted downtime due to neglected components. Furthermore, AC Today Maintenance Agreement Clients have repair priority status in the event that an emergency repair or replacement is needed.

Let AC Today keep you ahead of any AC System failures with our award-winning customized Maintenance Agreement.  Call us today for more information or stop by our headquarters to speak with our Maintenance Agreement Specialists!