A Fixie Home Improvement technician replacing a furnace filter in a home in St. Paul, MN

When to Replace Your Furnace Filters

Fixie Home Improvement

When the weather turns cold in Minnesota, the minds of many homeowners turn to staying warm and cozy inside. At least ours do. At Fixie Home Improvement, we know the value of preventative maintenance, so we wanted to share the simplest and most effective thing you can do to stay comfortable this winter – regularly change your furnace filter. Replacing the filter is simple enough to do yourself and only takes a few minutes, yet it can have a big impact on your home’s heating efficiency and air quality. After reading this blog post, you’ll have all the information you need to understand furnace filters and get started replacing them.

1.  Why Are Furnace Filters Important?

A side by side comparison of a clean furnace filter and one that needs to be replaced
Furnace filters play a vital role in maintaining a healthy and efficient home heating system. Their primary functions are:

Improved Air Quality

Furnace filters trap dust, debris, allergens, and pollutants, preventing them from circulating throughout your home. This is especially important if you or your family members suffer from allergies or respiratory issues.

Longer Equipment Lifespan

Clean filters allow your furnace to operate efficiently, reducing wear and tear on the system. This can help prolong the lifespan of your heating equipment and save you money on repairs or replacements.

Better Energy Efficiency

A clogged or dirty filter restricts airflow, making your furnace work harder to maintain the desired temperature. This not only drives up your energy bills but also reduces your home’s overall energy efficiency.

2.  How Often Should You Replace Your Furnace Filter?

The frequency of filter replacement largely depends on several factors, including:

Filter Type

Different types of filters have different lifespans. Standard fiberglass filters usually need replacement every 1-2 months, whereas high-efficiency filters can last up to 6-12 months.


Homes with pets or residents with allergies may require more frequent filter changes. The more your furnace runs, the more frequently the filter should be replaced.

Environmental Factors

If you live in an area with high levels of dust, pollen, or pollutants, your filter may become dirty more quickly. As a general rule of thumb, it’s a good idea to check your furnace filter every month and replace it as needed. Over time, you’ll get a better sense of how often replacement is necessary based on your specific circumstances.

3.  Signs it’s Time to Replace Your Furnace Filter

In addition to a regular maintenance schedule, keep an eye out for these telltale signs that your filter needs changing:

Reduced Airflow

If you notice weaker airflow coming from your vents, a clogged filter could be the culprit.

Increased Energy Bills

A dirty filter makes your furnace less efficient, which can lead to higher heating costs.

Visible Dirt and Dust

If you can see dirt and dust accumulating on the filter’s surface, it’s definitely time for a replacement.

Allergy Symptoms

If you or your family members start experiencing allergy symptoms or worsening respiratory issues, it might be due to an overdue filter change.

4.  How to Replace Your Furnace Filter

Replacing your furnace filter is a straightforward process:

Turn Off the Furnace

Ensure the furnace is powered off before attempting to replace the filter.

Locate the Filter

Typically, the filter is located in a slot near the blower motor. Consult your furnace’s manual if you’re unsure of its location.

Remove the Old Filter

Carefully slide out the old filter and dispose of it properly.

Insert the New Filter

Slide the new filter into place, following the airflow direction indicated on the filter frame.

Turn the Furnace Back On

Once the new filter is securely in place, turn the furnace back on, and you’re good to go.

Regularly replacing your furnace filter is a small, yet significant, step in maintaining a comfortable and energy-efficient home. By following the guidelines outlined in this blog post, you can ensure that your furnace operates at its best, providing you with clean, warm air and a more cost-effective heating system. If you have any questions or need assistance with your home’s heating system, don’t hesitate to reach out to us. We’re here to help you create a cozy and efficient living environment.

Related Articles