When and How to Change Your Furnace Filter

December 01, 2015

Caring for your furnace can help quite a bit in the time in between furnace service appointments. One of the most basic, and crucial, ways to care for your furnace is by switching out your furnace filter. Having a dirty air filter may contribute to a number 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 deciding 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 normally need to be replaced every month and 3 inch filters need to be replaced every three months, based on the recommendations of the filter manufacturer.
  • Home habits: if you have pets in your home, it may make sense to switch out your filter more often due to pet dander. If you have someone in the house that has allergies or asthma, think about changing your home’s air filter more frequently to help potentially decrease their symptoms.

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

  • Open or pull 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 you’ll see 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 pull down one end of the filter and take it out of the compartment.
  • When putting in the new filter, check the perimeter of the filter for an arrow that shows you the air flow direction, to ensure you’re installing the filter in the right direction. In nearly all cases, the arrow should point to the main part (or top) of the furnace. 
At Boehmers/Cronin Emery 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.