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This Is Why You Need to Change Your Furnace Filter

Changing furnace filters is a home maintenance task that is too often forgotten, much to the detriment of your HVAC system. When you operate your heating and cooling equipment with a dirty filter, you put your system, comfort, and budget at risk.

The Indianapolis HVAC professionals of Williams Comfort Air explain why changing furnace filters is so critical to your system. We also share some strategies to help you remember this important task. If you experience trouble with your heating and cooling equipment, contact us today for service.

What Is the Job of a Furnace Filter?

Most people think the furnace filter’s job is to remove contaminants from the air in order to provide cleaner indoor air quality. While this is a function of the furnace filter, it’s more like a great bonus because this is not the filter’s primary job.

The furnace filter’s job is to remove contaminants from the air that circulates throughout the HVAC system and your home, but not for air quality purposes. The furnace filter removes contaminants to keep them out of your heating and cooling systems. By removing airborne contaminants, the furnace filter helps protect the HVAC system’s sensitive components.

How Often Do I Need to Be Changing Furnace Filters?

How often you need to be changing furnace filters depends largely on the type of filter you use. Filters vary greatly on size and quality – take a look at your local home improvement store’s furnace filter aisle and you see a variety of different filters available!

How often changing furnace filters must be done ranges anywhere from once a month to once a year depending on the product! Filter manufacturers include a recommendation regarding how often the filter should be changed.

In general, 1-inch filters must be replaced more frequently than 5-inch filters; MERV 1 filters must be replaced more frequently than MERV 12 filters. While the actual recommendation varies by the filter, this is how often to be changing furnace filters based on their thickness:

  • 1-inch and 2-inch filters need to be changed every 1 to 3 months.
  • 3-inch and 4-inch filters need to be changed every 6 to 9 months.
  • 5-inch and 6-inch filters need to be changed every 9 to 12 months.

In addition to the filter’s thickness and quality, other factors affect how frequently changing furnace filters needs to be done. These factors include:

  • How many people live in your home? The more people in your household, the more frequently changing furnace filters needs to be performed. With more people, there are more contaminants brought into your air supply.

  • Are there any pets in your home? Pets like dogs and cats bring contaminants into the home on their fur. They also shed hair and dander which adds particles to your air supply. Every pet in the household lowers furnace filter lifespan by about 30 days.

  • What’s the quality of your indoor air? If you aren’t using other methods to control indoor air quality in the home, such as an air cleaner or purifier, the furnace filter is the only thing working to remove contaminants. Therefore, it doesn’t last as long as it would in a home with good indoor air quality.

  • Does anyone in your home suffer from allergies? If anyone in your household suffers from allergies, it’s wise to be changing furnace filters more frequently. This ensures allergens are trapped and removed from the house.

  • How often do you use your HVAC system? When the HVAC system runs more frequently, filters don’t last as long. Expect to be changing furnace filters more frequently in the summer and winter when the system is heavily used.

Problems That Arise When Changing Furnace Filters Is Forgotten

Not changing furnace filters creates a number of problems for Indianapolis homeowners. A dirty filter leads to issues with your HVAC equipment, air quality, and home comfort.

  • As the filter’s primary job is to protect HVAC system components from debris, this job is not fulfilled when the filter is dirty. When the filter is no longer capable of trapping contaminants, they continue to pass through and are able to settle within the system. This buildup impacts the performance of the system and has the ability to damage components within your heating and cooling equipment.

  • Without the ability to remove airborne contaminants, a dirty filter allows debris into the condensate drain of your system. They build up and cause clogs in the condensate drip pan and condensate drain lines. These clogs do not allow condensation to exit your home, which results in higher humidity levels within. A clog also allows excess condensation to leak out, which has the potential to cause water damage to your HVAC equipment and surrounding areas.

  • A dirty filter restricts airflow through your HVAC system. With a filter completely clogged with contaminants, the system’s fan consumes more energy in attempts to push air through. Excessive energy consumption leads to higher utility bills. Plus, this extra work causes more stress to the system, leading to breakdowns and damage.

  • When airflow is restricted by a dirty furnace filter, the home does not receive the heating and cooling needed to maintain comfort. Airflow restrictions caused by dirty filters lead to hot and cold spots throughout your living area and it becomes difficult to maintain temperatures throughout the house.

  • Dirty filters that restrict airflow also lead to overheating within a furnace or air handler. Without good air movement through the system, temperatures become too high and the equipment’s limit switch shuts down the system. Once it cools down, the system restarts, but quickly becomes overheated and shuts down again. This creates an issue called short-cycling, and dirty furnace filters are its most common cause. Short cycling causes damage to your HVAC system and leads to breakdowns as well as early system failure.

  • With the furnace filter also removing contaminants for cleaner indoor air, this bonus function does not occur when the filter is dirty. When a filter is no longer able to remove contaminants, they recirculate back into your living areas, which worsens allergies, causes respiratory symptoms, and makes your surfaces dirty.

Remembering Your Furnace Filter Changes

While changing furnace filters doesn’t always have to be done each month, it is a good idea to check the filter once a month. These filter checks allow you to assess the condition of the filter and replace it if it has become covered in contaminants. This way, the filter is changed as needed and the system isn’t stressed as it works waiting for that recommended interval.

Because changing furnace filters is so important to the health of your HVAC system and your family, it’s critical that you always remember to perform this task! The furnace is out of sight, so it’s often out of mind as well, which makes forgetting happen all too easily.

Avoid forgetfulness and the issues that come with a dirty furnace filter – try one of these strategies to keep changing furnace filters top of mind.

  • If you keep a wall calendar or day planner, pencil in changing furnace filters based on the manufacturer’s recommended interval. Also, plan dates to perform those quick monthly filter checks. You may find it helpful to also schedule the purchase of replacement filters, so you have them on hand when it’s time for changing furnace filters.

  • Use the calendar app on your smartphone and set reminders for changing furnace filters just as you would on a written calendar. You can even schedule alerts some time before, so you remember to buy a replacement filter ahead of the scheduled filter change.

  • If you have a household or home improvement to-do list, make sure changing furnace filters is on it. While we think we will remember such an important task, often that’s not the case – write it down where you reference the other tasks you have to do around the home.

  • Make changing furnace filters a part of your process for associated tasks, such as paying your utility bills each month. When you receive that bill or submit that payment, don’t consider the task complete until you’ve also checked or changed your furnace filter.

  • Purchase replacement furnace filters ahead of time and write the month or date changes are due on the frame of the filter. This helps you stay on top of scheduling filter changes, and you’ll know exactly when it’s time to throw out your old filter and replace it with a new one.

HVAC Help from Williams Comfort Air

Professional HVAC tune-ups ensure your system starts the season with a fresh and clean filter and removes built-up dirt and debris that has gathered within your equipment over the past year. Schedule your maintenance tune-up today to receive this important cleaning plus much more!

If changing furnace filters hasn’t happened on the regular in your household and you experience any of the system issues discussed above, call Williams Comfort Air for heating repair today. Our NATE-certified technicians evaluate your equipment to pinpoint problems and make accurate repairs to restore your system’s performance.

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