What you need to know about your air conditioning filters
By: Jenny Remlinger
Your A/C filter needs to be checked, maintained and changed frequently in order to function properly and safely. Maintaining your A/C filter preserves the life of your A/C unit, saves money on your electricity bill and provides a healthier living environment.
What filters do I need?
There are so many different sizes and types of filters on the market that it may be overwhelming and a bit confusing. Not everyone can use the standard 1-inch filter you commonly see. Sometimes a 2-, 4-, 5- or 6-inch filter is required, like Glasfloss, Honeywell, Aprilaire, Trane, Lennox or Carrier, to name a few. Some filters are used in a filter grill located on your wall or ceiling. Or it may be in a housing unit attached to your unit located in a closet, attic or garage.
Most homes have one unit that requires a main filter, and in some cases, they may have a prefilter or two-plus filter grills that require filters. When purchasing a home, always find out where the filter is located, how many are needed and which types are best for the unit. Some A/C companies put a label on the inside of the unit door or cabinet of the filter housing to let you know what kind of filter the unit requires.
How often should I change my filter?
In the large chain stores, a common 1-inch filter reads “90-day filter,” but there are various reasons that isn’t always the case. The frequency with which you change your filter depends on the climate, the location of you home and if you have pets. You need to change your filter more often if you live in warmer, humid climate, live in a dusty area like in the open country, near construction, etc., and/or if you have pets inside your home.
The quality and thickness of your filter will also help determine its longevity. Every home and lifestyle is different. If you live here in South Texas, where it is hot and dusty many months of the year, the recommended change time for a 1-inch filter is usually every 30 days, but ask your local filter specialist for more details, especially if you use a different type of filter.
Does filter quality matter?
Yes! Not all filters are created equal.
Fiberglass versus Polyfiber: Most hardware and grocery stores carry a 1-inch fiberglass filter for around a dollar. A fiberglass filter has an industry slang term of “rock catcher” because the filter media is so loosely woven that you can see through it and it practically only catches particles the size of rocks. A specialty filter store will carry a polyfiber and pleated filter. Polyfiber filters are a better choice than fiberglass because the fibers are more closely woven to catch smaller particles while still allowing the air to pull through easily.
Pleated filters: What’s the scoop? Pleated filters collect more particles than polyfiber filters. Those concerned with air quality, like people with allergies or asthma, may want to use a quality pleated filter instead of a polyfiber because it will help filter out more dust, dander and other particles. However, not all pleated filters are the same. Pleated filters have different Merv ratings and structure. You may find a pack of two or three pleated filters at a big chain store are the same cost as one pleated filter at a specialty store. Most likely it is due to the Merv rating and the type of material used to make the filter.
When your unit turns on and pulls air through the filter, you don’t want a flimsy, loosely woven filter to bend or fold and let the particles in the air pass through and around the edges of the filter and onto the coils. The higher the Merv rating, the more particles the filter will collect, but you have to be careful because it also means more air is restricted. The higher the Merv rating, the more strain there will be on your unit, and that can cause it to fail earlier than expected and run up your electric bill.
Changing your filter more regularly may seem expensive at the time, but it will save you money in the long run.