When and How to Change Your Furnace Filter

December 01, 2015

Taking care of your furnace can go a long way in the months in between furnace service appointments. One of the easiest, and essential, ways to take care of your furnace is by changing your furnace filter. Having a clogged air filter could contribute to a variety of unfavorable concerns for your heating and cooling system, its efficiency, and ultimately, how much you’re spending on your energy bills every month.

So what goes in to determining when you should replace 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 changed every month and 3 inch filters ought to be swapped out every three months, based on the recommendations of the filter manufacturer.
  • Home habits: if you have pets in your home, it may 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, think about replacing your home’s air filter more frequently to help ease their symptoms.

Now you’re probably wondering how to change your furnace filter. More than likely, 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’ll see your furnace filter 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 putting in 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 the majority of cases, the arrow should point to the main part (or top) of the furnace. 
At A-PLUS Service Experts Heating & Air Conditioning, we’ll change 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 set up an appointment with us online.