When and How to Change Your Furnace Filter

December 01, 2015

Maintaining your furnace can help quite a bit in the period in between furnace service appointments. One of the most basic, and crucial, ways to maintain your furnace lies in replacing your furnace filter. Having a clogged air filter could contribute to a number of negative problems for your heating and cooling system, its efficiency, and ultimately, how much your energy costs are month after month.

So what goes in to consideration when you should switch out 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 need to be replaced every three months, dependent on the recommendations of the filter manufacturer.
  • Home habits: if you have pets in your home, it may make sense to replace your filter more often due to pet dander. If someone in your family has allergies or asthma, think about changing your home’s air filter more frequently to help with their symptoms.

Now you’re likely wondering how to replace your furnace filter. More than likely, this will vary depending on what furnace you have, but usually: 

  • Open or take off the air filter panel close to 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 lips.
  • There will be a small amount of space to move your filter back and forth that allows you to bring down one end of the filter and take it out of the compartment.
  • When adding the new filter, look at the perimeter of the filter for an arrow that specifies the air flow direction, to make sure you’re installing the filter in the right direction. In most cases, the arrow should point at the main part (or top) of the furnace. 
At D.A. Bennett 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 arrange an appointment with us online.