When and How to Change Your Furnace Filter

December 01, 2015

Maintaining your furnace can help more than you’d think in the time in between furnace service appointments. One of the simplest, and crucial, ways to take care of your furnace lies in changing your furnace filter. Having a filthy air filter could contribute to a number of adverse issues for your heating and cooling system, its efficiency, and ultimately, how much your energy expenses are each 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 swapped out every three months, dependent 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 as a result of pet dander. If a family member deals with allergies or asthma, contemplate switching out your home’s air filter more often to help ease 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 typically: 

  • 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 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 putting in the new filter, look at 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 right direction. In the majority of cases, the arrow should point towards the main part (or top) of the furnace. 
At Strand Brothers 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 arrange an appointment with us online.