If you want your home HVAC system to be as efficient as possible, you must regularly change your air filter. However, many homeowners are unaware of how often air filters need to be changed. This guide explains how often to change an air filter in your home.
A dirty air filter not only reduces the efficiency of your furnace but, more importantly, negatively impacts the quality of the air you and your family breathe.
But how often should I change my air filter? The correct answer is: it depends.
Many manufacturers recommend that you change your HVAC filter every three months. But this is only meant as a guideline. As you might have guessed, every household is different.
Factors to consider when determining when to change your air filter.
A variety of factors may determine how often you change your filter. They include:
- The type of air filter
- Specific conditions in the home:
- Home size
- Pets
- Allergies
- The air pollution around your home
For residential applications, standard disposable polyester or pleated air filters should be checked every three months. Often after that length of time, a filter will require a change.
However, environmental factors such as pet hair, heavy foot traffic in your home, and tobacco smoke can decrease the life of your furnace filter and require a more frequent change.
Here is a table that may help you know how often you should change your air filter in your home:
| home without pet | every 3 months |
| 1 pet | every 2 months |
| more than 1 pet | every 30 days |
| has allergies | every 20 days |
For higher efficiency air filters or another type of media air cleaner, the lifespan can range from 6 months to one year. Commercial applications have an even broader spectrum of change-out frequencies.
Air filters in restaurants are commonly changed every 4 to 8 weeks, depending on the customer traffic and filter type. Retail chains, strip malls, and other small businesses vary but need a change every 12 weeks.
Industrial facilities, depending on the nature of their business, often require a filter replacement every week. Plants with heavy smoke, soot, and other airborne contaminants need a massive filtration system, and with all the pollutants in the air, the filters can quickly become saturated.
What happens when you don’t change the air filter?
Do Dirty Air Filters Increase My Energy Bills? Yes!
As your air filters get dirty, they begin to restrict the air flowing through the unit. This causes the HVAC unit to work harder to maintain sufficient airflow. It uses more electricity, which can dramatically increase your utility costs over time.
In addition, dirt acts as an insulator disrupting the heat transfer of the air flowing through the unit. This also causes your heating and cooling unit to work harder, which uses more electricity.
Not regularly changing your air filters can also lead to costly mechanical breakdowns. Keeping your air filters clean is truly the most cost-effective way to maintain your HVAC equipment and a cleaner environment around your home.
