When and How to Change Your Furnace Filter

December 01, 2015

Taking care of your furnace can help more than you’d think in the period in between furnace service appointments. One of the simplest, and critical, ways to take care of your furnace lies in replacing your furnace filter. Having a clogged air filter may contribute to a host of adverse issues for your heating and cooling system, its efficiency, and ultimately, how much your energy expenses are every month.

So what goes in to consideration 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 usually need to be changed every month and 3 inch filters ought to be replaced every three months, depending on the recommendations of the filter manufacturer.
  • Home habits: if you have pets in your home, it might make sense to replace your filter more often because of pet dander. If you have someone in the house that suffers from allergies or asthma, think about switching out your home’s air filter more regularly to help potentially decrease their symptoms.

Now you’re likely wondering how to change your furnace filter. Obviously this will vary depending on what furnace you have, but normally: 

  • Open or remove the air filter panel close to 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 supports.
  • 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 pull it out of the compartment.
  • When adding the new filter, look at the perimeter of the filter for an arrow that indicates the air flow direction, to be sure you’re installing the filter in the proper direction. In nearly all cases, the arrow should point to the main part (or top) of the furnace. 
At Roy Inch & Sons 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 set up an appointment with us online.