When and How Often to Change Your Furnace Filters

Maintaining a comfortable and energy-efficient home is a top priority for any homeowner. One often overlooked aspect of this equation is the furnace filter. While it might seem like a minor detail, the furnace filter plays a crucial role in ensuring indoor air quality, extending the lifespan of your HVAC system, and optimizing energy consumption. This article delves into the importance of changing your furnace filters, how often it should be done, and the steps to follow for a seamless process.

Why Change Your Furnace Filter?

The furnace filter is responsible for trapping dust, debris, allergens, and other particles in the air before they can circulate throughout your home. Over time, these particles accumulate on the filter, causing it to become clogged and less effective. A dirty or clogged filter can result in several issues:

  1. Reduced Indoor Air Quality: A clogged filter can’t effectively capture pollutants, leading to poor indoor air quality and exacerbating allergies and respiratory issues.
  2. Decreased Energy Efficiency: When the filter is clogged, the furnace has to work harder to push air through the system, leading to increased energy consumption and higher utility bills.
  3. Shortened HVAC Lifespan: The strain on your HVAC system caused by a clogged filter can lead to premature wear and tear, reducing the equipment’s overall lifespan.
  4. Uneven Heating/Cooling: A clogged filter can disrupt the even distribution of heated or cooled air throughout your home, leading to uncomfortable temperature variations.

How Often Should You Change Your Furnace Filter?

The frequency of changing your furnace filter depends on several factors:

  1. Type of Filter: Different filters have varying lifespans. Basic fibreglass filters may need to be replaced every 1 to 3 months, while higher-quality pleated filters can last up to 6 months.
  2. Indoor Air Quality: If you have pets, allergies, or live in an area with high levels of dust or pollen, you might need to change the filter more frequently.
  3. Usage: If your HVAC system runs constantly, you might need to change the filter more often than sporadically.
  4. Manufacturer’s Recommendations: Always refer to your HVAC system’s manual for specific guidelines on filter replacement.

Steps to Change Your Furnace Filter

Changing your furnace filter is a straightforward process:

  1. Turn Off the HVAC System: For safety, turn off your furnace before attempting to replace the filter.
  2. Locate the Filter: The filter is typically near the air intake or the blower compartment. Refer to your system’s manual if you’re unsure.
  3. Remove the Old Filter: Slide out the old filter, taking note of its size and airflow direction. This information will be crucial when installing the new filter.
  4. Insert the New Filter: Slide the new filter in, ensuring it’s placed in the same direction as the old filter. An arrow on the frame usually indicates the airflow direction.
  5. Turn On the HVAC System: You can turn your furnace back on after successfully replacing the filter.


Regularly changing your furnace filter is a simple yet effective way to maintain indoor air quality, optimize energy efficiency, and prolong the life of your HVAC system. By understanding the factors that influence the frequency of filter changes and following the proper steps, you can ensure that your home remains comfortable, healthy, and cost-efficient year-round. Remember, a clean filter benefits your family’s well-being and contributes to a greener and more sustainable living space.

Share This Post


Scott Tizzard

President & Founder

Since 2013 I have been helping Canadians by providing the best in class heating and cooling solutions for their homes and businesses. I am hands on with my business and take pride in our work and craftsmanship. We look forward to taking care of your needs. Feel free to contact me directly.