When and How to Change Your Furnace Filter

December 01, 2015

Maintaining your furnace can go a long way in the period in between furnace service appointments. One of the simplest, and critical, ways to take care of your furnace is in replacing your furnace filter. Having a filthy air filter can contribute to a number of negative concerns 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 replace 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 ought 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 because of pet dander. If you have someone in the house that suffers from allergies or asthma, consider replacing your home’s air filter more often to help with their symptoms.

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

  • Open or pull off the air filter panel close to the bottom of your furnace to expose 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 little 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 installing the new filter, inspect the perimeter of the filter for an arrow that indicates the air flow direction, to ensure you’re installing the filter in the correct direction. In most cases, the arrow should point at the main part (or top) of the furnace. 
At A1 Chesney 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 schedule an appointment with us online.