How Often do Furnace Filters Need to be Replaced?

Furnace filters help to maintain the indoor air quality in your home, ensuring that you have a comfortable environment. They trap airborne particles such as mold spores, pet dander, dust and other allergens. However, soot, mold spores and dirt accumulate in the filter over time. This leads homeowners to ask: “How often do furnace filters need to be replaced?”

Specialists from Mitchell Heating can inspect your home’s HVAC system to ensure it is running optimally. We can check your filters, air conditioner, furnace and other components efficiently and quickly. Our subject matter experts can also give you tips and advice to keep your systems running in top shape.

In the discussion below, you’ll learn about the role furnace filters play in your HVAC system, factors that affect their lifespan and the telltale signs that you need a filter replacement.

Factors Influencing Filter Lifespan

We must determine the factors impacting their usable life to know how often furnace filters need to be replaced. Filters are designed to capture and remove airborne particles circulating through an HVAC system.

Filters are made from porous materials such as polyester, pleated paper, fiberglass or other electrostatic materials. They are installed near an HVAC’s intake to capture and block air particulates effectively. By doing so, they remove airborne pollutants and improve indoor air quality. The electrostatic charge and filter fibers attract the particles preventing them from circulating within the system. This promotes better living conditions since contaminants in the air are removed.

Just like any fixture in a heating or cooling system, furnace filters have a usable life, which can be affected by several factors:

  • Filter Build Quality: The quality of the filter installed in your HVAC system can be a significant factor when determining its service life. High-quality filters are better at getting rid of particulates, and they’re designed to be more efficient and durable. Filters with higher MERV ratings can capture smaller airborne particles, but their finer filtration media can get clogged faster. Always consider the specifications of the filters to determine their usable life.
  • Concentration of Air Pollutants: If you live in an area with higher pollutant concentration, expect to replace filters more often. If you smoke indoors, have pets inside your home or live in construction areas, expect your filters to get clogged faster.
  • Frequency of Furnace Usage: The filter’s lifespan will become shorter with more frequent furnace usage, especially during the peak warming or cooling seasons.

How Often Do Furnace Filters Need to be Replaced?

Most furnace filters need to be replaced every 90 days. If your furnace uses a permanent filter, it will require frequent cleaning and not a replacement. Following this replacement schedule, you can keep harmful air particles from entering your furnace’s internal components.

Failing to follow this schedule can result in a filter full of gunk and debris. When this happens, the furnace’s airflow gets restricted, reducing your unit’s performance. In worse cases, it can even lead to a breakdown of your home’s HVAC.

Before this three-month replacement schedule, inspecting the filters every 30 days or once a month is crucial. With this maintenance check, you can identify potential issues before they become major problems. Check for leaks and see if the furnace is blowing cold air.

It is important to note that your filter may need replacement earlier than 90 days. You may have to replace filters in 30 to 60 days, depending on the air quality of your home.

Telltale Signs That Your Furnace Filter Needs a Replacement

As mentioned, some conditions require replacing your furnace filters earlier than the usual three-month schedule. Paying attention to the signs your filter may already be clogged will help you maintain your HVAC system, ensuring it runs efficiently.

Pay attention to the following indicators of the need for a filter replacement:

  • Reduced Airflow: One of the most common signs that your furnace filters are already clogged is a reduction in the airflow. Check the vents and see if the airflow is uneven, the same as it used to be. If the filters are clogged, the air from some of the vents will feel weaker, which tells you that there’s restricted airflow.
  • Poor Indoor Air Quality: When the filters are clogged and airflow is reduced, the air quality in your home will also be affected. With more particulates entering your home, you may have an increased dust accumulation on many surfaces. You can also experience frequent respiratory symptoms such as cough and allergies.
  • Foul Odors: A clogged or dirty furnace filter can also contribute to foul odors coming from your HVAC system. When you turn on your heating or cooling system, it can begin as a stale or musty odor. The smells can worsen if the furnace filters aren’t replaced soon enough. Sometimes the foul odors are accompanied by banging, whistling or rattling noises, which may indicate the need for a furnace replacement.
  • Increased Energy Consumption: One of the signs that your furnace’s filters may already be clogged is an unexplained increase in your monthly energy bill. When the filters are clogged, it can lead to decreased HVAC efficiency. This means your system will work harder than it used to meet your home’s heating requirements. Replacing the filter restores optimal airflow within the system, increasing your unit’s energy efficiency.

Extending the Lifespan of Furnace Filters

There are a few things you can do to extend the lifespan of furnace filters so you don’t need to replace them sooner:

  • Make an Effort to Improve Indoor Air Quality: Doing your part to improve the air quality in your home will help extend the lifespan of furnace filters. Regular vacuuming, house cleaning, pet grooming, ensuring proper ventilation and avoiding smoking indoors will help.
  • Duct Cleaning and Sealing: Inspect ducts for air leaks, debris and dirt build-up. This can help prevent contaminants from entering your home and reduce the load on your HVAC and furnace filters.
  • Use Air Purifiers: Installing standalone air purifiers can help reduce the strain on your heating system. They can be installed strategically in specific rooms of your house, which can enhance air filtration.

Trust the Heating Specialists At Mitchell Heating

Your furnace filters need to be inspected regularly to ensure they’re running optimally. Mitchell Heating certified technicians have proudly served Colorado residents for over 25 years. We are the brand to trust when it comes to furnace installation, maintenance and repair. Contact us today to request an estimate or service.