When and How to Change Your Furnace Filter

December 01, 2015

Maintaining your furnace can help quite a bit in the months in between furnace service appointments. One of the simplest, and essential, ways to maintain your furnace is in replacing your furnace filter. Having a clogged air filter could contribute to a number of unfavorable problems for your heating and cooling system, its efficiency, and ultimately, how much your energy costs are every 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 replaced every month and 3 inch filters should be swapped out every three months, based on the recommendations of the filter company.
  • Home habits: if you have pets in your home, it may make sense to change your filter more often due to pet dander. If you have someone in the house that has allergies or asthma, contemplate replacing your home’s air filter more frequently to help with their symptoms.

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

  • Open or remove the air filter panel near the bottom of your furnace to uncover an open compartment.
  • On the top of that open compartment is where your furnace filter is resting on two metal supports.
  • There will be a bit 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 installing the new filter, inspect the perimeter of the filter for an arrow that specifies the air flow direction, to make sure you’re installing the filter in the correct direction. In nearly all cases, the arrow should point to the main part (or top) of the furnace. 
At Freschi 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 set up an appointment with us online.