When and How to Change Your Furnace Filter

December 01, 2015

Maintaining your furnace can go a long way in the period in between furnace service appointments. One of the most basic, and critical, ways to care for your furnace lies in changing your furnace filter. Having a filthy air filter could contribute to a variety of negative concerns for your heating and cooling system, its efficiency, and ultimately, how much you’re spending on your energy bills each month.

So what goes in to deciding when you should change your furnace filter?

  • Type of filter: the two most common filter sizes are 1 inch and 3 inch filters. 1 inch filters typically need to be changed every month and 3 inch filters should be swapped out every three months, depending on the recommendations of the filter manufacturer.
  • Home habits: if you have pets in your home, it may make sense to change your filter more often due to pet dander. If a family member suffers from allergies or asthma, consider switching out your home’s air filter more regularly to help with their symptoms.

Now you’re possibly wondering how to swap out your furnace filter. More than likely, this will change depending on what furnace you have, but typically: 

  • Open or take off the air filter panel near the bottom of your furnace to expose an open compartment.
  • On the top of that open compartment is where you’ll see your furnace filter resting on two metal lips.
  • There will be a small amount of space to move your filter back and forth that allows you to pull down one end of the filter and remove it from the compartment.
  • When adding the new filter, inspect the perimeter of the filter for an arrow that shows you the air flow direction, to ensure you’re installing the filter in the proper direction. In most cases, the arrow should point at the main part (or top) of the furnace. 
At All American Air Service Experts Heating & Air Conditioning, we’ll change out standard one-inch furnace filters as part of our regular furnace service Precision Tune-up or PLUS Maintenance Agreement service. Give us a call today at or set up an appointment with us online.