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 simplest, and crucial, ways to take care of your furnace is by switching out your furnace filter. Having a filthy air filter may contribute to a variety of unfavorable issues for your heating and cooling system, its efficiency, and ultimately, how much your energy expenses are every month.

So what goes in to deciding when you should replace 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 should be changed every three months, dependent on the recommendations of the filter manufacturer.
  • Home habits: if you have pets in your home, it might make sense to change your filter more often because of pet dander. If someone in your family suffers from allergies or asthma, think about changing your home’s air filter more often to help ease their symptoms.

Now you’re possibly wondering how to swap out your furnace filter. Obviously this will differ depending on what furnace you have, but usually: 

  • Open or take off the air filter panel around the bottom of your furnace to reveal an open compartment.
  • On the top of that open compartment is where your furnace filter is resting on two metal brackets.
  • There will be a small amount of space to move your filter back and forth that allows you to remove one end of the filter and remove it from the compartment.
  • When adding the new filter, look at the perimeter of the filter for an arrow that shows you the air flow direction, to make sure you’re installing the filter in the correct direction. In most cases, the arrow should point at the main part (or top) of the furnace. 
At Fras-Air/General Service Experts Heating & Air Conditioning, we’ll replace 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.