How Often Should I Change My AC Filter?

How often should you change your AC filter? If you’re Googling this topic, it’s a pretty safe bet that the answer is way more often than you do now. The filter in your HVAC system is there to limit the amount of dust and contaminants entering your home. Filtering pollutants and allergens out of the air you breathe also helps protect you from getting sick, so dirty AC filters mean more polluted air circulating in your home. A dirty air filter can also lead to breakdowns in your equipment due to dirt and grime build-up on important system components.

Whether you’re renting or you own your own home, changing your AC filter is easy to forget because AC filters are not part of your everyday view. You can’t see them, so you can’t see how dirty they are becoming. Additionally, we’re often busy worrying about much more “important” tasks around our home than changing out a filter. That’s completely understandable. However, regularly changing your AC filter should be a priority. Dirty AC filters can harm the overall health of you and your family, and reduce the efficiency and lifespan of your HVAC system.

Pro Tip: Change AC filters on the first of every month, or set a reminder in your calendar.

How Often Does an AC Filter Need to be Changed?

That depends. The number of people and pets in your home will determine how often you should replace your air filters. As a general rule, HVAC manufacturers recommend the following:

  • If you or anyone in your family has severe allergies, change your AC filters once a month. 
  • If you have two or more pets in your home, have your AC filters replaced every month. 
  • The average household should replace AC filters at least every 2 to 3 months or whenever the filter is dirty.

Regularly changing your AC filters will help prevent a spike in allergies, and help avoid anyone in the home from getting sick or a spread of germs. Your HVAC system will operate more efficiently, too.

Which AC Filter Should I Buy?

Before purchasing AC filters, always check what size you need as there are several different sizes for different homes. The type of AC filter you buy will depend on your particular needs and your budget.

Fiberglass Filters

Fiberglass filters are the most common air conditioning filter, and the least expensive. Fiberglass filters only remove large, damaging particles in the air, so they are not effective in improving air quality.

Polyester and Pleated Air Conditioning Filters

Polyester and pleated air conditioning filters remove about 45% of dust and other small particles from the air.

High-Efficiency Particulate Air Filters (HEPA)

HEPA filters remove the most harmful contaminants from the air, including dust and mold. HEPA filters in HVAC systems ore often used in industrial and medical facilities. However, it is not unheard of for homeowners with severe allergies or illnesses to use them.

Electrostatic Filters

Electrostatic filters remove unwanted particles in the air using static electricity. Unlike polyester and fiberglass filters, electrostatic filters are permanent, and only need to be washed every three months or so. They can be 2 to 6 times more expensive than a typical air conditioning filter. Since you won’t need to replace it, that cost quickly pays for itself.

How Do I Change My Air Filter?

Changing an air filter in your home is a straightforward and quick task that should take no longer than a few minutes. Unscrew the vent cover, remove the old filter, and replace it with a new one. It’s really that simple!