When to Change Air Filters in Your Home

Before discussing when to change the air filter in your home, let’s take a moment to stress the importance of this often forgotten task.

Why changing air filters is important

HVAC air filters reduce the amount of dust, mold, pet dander and other allergens in the air your family breathes inside your home. But did you know that in addition to improving indoor air quality, changing the air filters is vital to keeping your heating and cooling system running efficiently and effectively?

Clogged air filters can reduce the airflow in your home, which forces your system to work harder to take in the proper amount of air to cool/heat your home. This can cause higher utility bills and can even cause your system to malfunction or fail completely.

For example, think back to a home improvement project that required you to wear a breathing mask over your nose and mouth. At the beginning of the project, when the mask was fresh and clean, breathing was comfortable and easy. As the project progressed, and the mask became dusty and dirty, breathing was more difficult and uncomfortable. The same idea applies to home air filters. Changing your filter when needed helps keep your system running smoothly and prevent costly repairs.

Determining when to change your air filters

How often should air filters be changed? The short answer is if your filter is dirty, it’s time to change it – no matter how long it has been since it was installed. The amount of time it takes to get dirty depends on the specifics of your home and system. Here are some guidelines to help you determine the best answer for you and your home.

1. Determine what kind of filter your HVAC system requires. If your system uses the 1-3” thick air filters common in most hardware store aisles, most manufacturers suggest changing the filters at least every 60 days.
2. Does anyone in the home suffer from allergies? If so, you will want to change the filters sooner than the manufacturer recommends. When a filter is clogged, instead of filtering allergens from the air, it can start to spread dust and other particles inside your home. Consider changing filters every 30-45 days.
3. Does your household have pets? If you share your home with a furry friend, your filters will contain pet dander and animal hair which will clog the filter faster. Homes with pets – especially multiple pets – should change filters more frequently, such as every 30-45 days.
4. What is the outdoor air quality where you live? If there is construction nearby that is kicking up a lot of dust and debris, you will need to change your filters more frequently.
5. How frequently do you use your air conditioner/heater? Air filters only clean the air when the HVAC system is operating. In vacation homes or other seldom-used properties where the system is dormant for extended periods of time, the filters can go considerably longer before they need to be replaced. In these instances, once or twice a year may be sufficient.

Remembering to change your air filters

Once you have determined when your system’s filters should be changed, it’s time to set up a system.

• Put a recurring reminder on your calendar or in your phone or email.
• Choose a consistent day – like the first of the month – to you keep track of the amount of time between filter changes. Or use your utility bill as a memory prompt to change your filters.
• Buy several filters at a time, so that you will always have some on hand when needed.
• Remember: this quick and simple act of maintenance will help your family breathe easier and prevent costly repairs in the future.