When and How to Change Your Furnace Filter in North America

Maintaining your furnace can help more than you’d think in the period in between furnace service appointments. One of the easiest, and essential, ways to take care of your furnace is in switching out your furnace filter. Having a dirty air filter can contribute to a variety of negative 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 change 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 switched out every month and 3 inch filters should be swapped out every three months, dependent on the recommendations of the filter company.
• Home habits: if you have pets in your home, it could make sense to switch out your filter more often as a result of pet dander. If a family member has allergies or asthma, think about changing your home’s air filter more often to help with their symptoms.

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

• Open or remove 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 will find your furnace filter resting on two metal lips.
• 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 pull it out of the compartment.
• When adding the new filter, check the perimeter of the filter for an arrow that indicates the air flow direction, to make sure you’re installing the filter in the right direction. In most cases, the arrow should point towards the main part (or top) of the furnace.