When and How to Change Your Furnace Filter

December 01, 2015

Caring for your furnace can help more than you’d think in the months in between furnace service appointments. One of the most basic, and critical, ways to care for your furnace is by changing your furnace filter. Having a clogged air filter can contribute to a host of negative concerns for your heating and cooling system, its efficiency, and ultimately, how much your energy expenses are month after 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 normally need to be changed every month and 3 inch filters need to be changed every three months, dependent on the recommendations of the filter maker.
  • Home habits: if you have pets in your home, it may make sense to switch out your filter more often because of pet dander. If someone in your family deals with allergies or asthma, think about switching out your home’s air filter more regularly to help with their symptoms.

Now you’re probably wondering how to change your furnace filter. Inevitably this will change depending on what furnace you have, but typically: 

  • Open or pull off the air filter panel near the bottom of your furnace to uncover an open compartment.
  • On the top of that open compartment is where you will find your furnace filter resting on two metal supports.
  • There will be a little space to move your filter back and forth that allows you to bring down one end of the filter and pull it out of the compartment.
  • When putting in the new filter, look at the perimeter of the filter for an arrow that indicates the air flow direction, to make sure you’re installing the filter in the right direction. In most cases, the arrow should point to the main part (or top) of the furnace. 
At Bob Brown Service Experts, we’ll swap 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 schedule an appointment with us online.