When and How to Change Your Furnace Filter

Caring for your furnace can help more than you’d think in the time in between furnace service appointments. One of the easiest, and critical, ways to maintain your furnace lies in replacing your furnace filter. Having a dirty air filter can contribute to a variety of adverse 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 determining 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 switched out every month and 3 inch filters need to be replaced every three months, depending 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 as a result 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 frequently to help with their symptoms.

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

• Open or take off 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 pull it out of the compartment.
• When adding the new filter, check the perimeter of the filter for an arrow that shows you the air flow direction, to be sure you’re installing the filter in the correct direction. In nearly all cases, the arrow should point towards the main part (or top) of the furnace.