When and How to Change Your Furnace Filter

Caring for your furnace can help more than you’d think in the months in between furnace service appointments. One of the simplest, and essential, ways to care for your furnace lies in changing your furnace filter. Having a clogged air filter can contribute to a number of negative concerns for your heating and cooling system, its efficiency, and ultimately, how much your energy costs are each month.

So what goes in to determining 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 switched out every month and 3 inch filters should be swapped out every three months, based on the recommendations of the filter manufacturer.
• Home habits: if you have pets in your home, it could 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 replacing your home’s air filter more regularly to help with their symptoms.

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

• Open or take off the air filter panel around 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 brackets.
• There will be a small amount of space to move your filter back and forth that allows you to remove one end of the filter and take it out of the compartment.
• When adding the new filter, look at the perimeter of the filter for an arrow that shows you the air flow direction, to make 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.