When and How to Change Your Furnace Filter

December 01, 2015

Taking care of 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 care for your furnace is by replacing your furnace filter. Having a clogged air filter can contribute to a host of adverse concerns for your heating and cooling system, its efficiency, and ultimately, how much your energy costs are month after 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 switched out every month and 3 inch filters need to be replaced 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 switch out your filter more often due to pet dander. If you have someone in the house that deals with allergies or asthma, consider replacing your home’s air filter more often to help with their symptoms.

Now you’re probably wondering how to replace your furnace filter. More than likely, this will change depending on what furnace you have, but typically: 

  • Open or take off the air filter panel close to 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 lips.
  • 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 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 correct direction. In nearly all cases, the arrow should point to the main part (or top) of the furnace. 
At Roland J. Down Service Experts Heating & Air Conditioning, we’ll replace 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.