How Often Should I Change My Air Filter?

Replacing Your Home’s Air Filter

After the installation and careful balancing of a new central air conditioning system, many of our customers ask us, “How often should I change the air filter?” No one answer fits every household, but in general you should change your air filter monthly during cooling season, but more often under some circumstances. If you have a forced-air furnace, with the same question, “How often to change air filters,” you get the same reply: monthly, except…

Monthly

Most disposable air filters work primarily on the leading surface of the filter. Few particulates get much past the first few millimeters of the spun filter material, so the surface area for airflow starts to diminish as soon as the filter goes into service. This means after some 30 days of day-in, day-out filtration, your disposable filter is clogged at the surface (though the back side of it may appear spotless).

Since dirt and debris inhibit airflow, the more frequently you change your air filter, the happier your system will be. It will last longer, need fewer AC repairs, provide more efficient service and cost you less to run. Disposable filters are a few dollars each; your central air conditioner or Phoenix furnace system is an investment worth thousands.

Spend a bit now and again to save over the life of your system. You will also face lower maintenance costs for the heavier hardware with these regular outlays on the least expensive part of your cooling system.

More than Monthly

If your home faces the following circumstances, consider replacing your filter every three weeks, or even more often, for maximum comfort:

• Indoor Air Quality: If you face odors, stale air, smokers or other challenges to clean indoor air, replace your filters frequently.
• Pets: Pet dander can be swept up and caught on the filter, adding to rapid buildup; consider biweekly (every two weeks) replacement.
• Crowded home: A lot of people under one roof will tax a filter.
• Surrounding air: Poor outdoor air quality means particulates come in on clothes and shoes, adding to the filter’s work.
• Special needs: Homes with allergy sufferers or family members with compromised respiratory systems should even consider weekly filter replacement or cleaning.

Less Often?

For homes with no pets, vacation homes, homes with only a single occupant or homes surrounded by pristine air (at mountain elevations, for example), you can get away with filter changes every six to eight weeks.

Ask the Experts

Air filter replacement need not be guesswork. Contact one of the best Phoenix air conditioning companies, Howard Air & Plumbing, for a professional consultation. We can teach you how often to change air filters and assess your home’s indoor air quality.