Should You Change Your Furnace Filter Before Every Winter Season?

The furnace filter is a key component of forced air heating and cooling systems, like a furnace or heat pump. The air filter works to protect equipment from damaging dust, dirt, and other matter, while maintaining proper airflow through the system. As an added bonus, filters also keep indoor air cleaner as they remove airborne particles from circulation.

Throughout the winter (as well as the rest of the year), you need to change furnace filter media and replace it with a new filter often. Williams Comfort Air shares why it’s important to change a furnace filter regularly, as well as how often to check and change your furnace filter. These tips help you remove and replace filters the right way to ensure the filter functions correctly.

Why Change the Furnace Filter?

As a homeowner, it’s important that you change your furnace filter as part of the routine maintenance your heating and cooling system requires. This air filter may be disposable or reusable, though disposable filters are most common. Even when filters are frequently changed, many homeowners do not know their true purpose.

As mentioned above, the furnace filter’s purpose is to remove dirt, dust, and other particulates from the air that circulates through the HVAC system. Furnaces and air handlers are filled with many delicate components and their function can be disrupted when they become dirty or covered in a layer of grime. When you install a new filter, it provides the protection these components need to maintain performance and energy efficiency. In turn, energy costs are reduced and the system lasts longer.

An HVAC filter primarily removes airborne particulates for the benefit of the heating unit – however, this process also benefits indoor air quality. By trapping contaminants, the home’s air quality is cleaner. Filters with higher MERV (minimum efficiency reporting value – the measure that reflects a filter’s ability to remove contaminant particles of different sizes) ratings are more effective at capturing smaller particles, keeping them out of the indoor air supply. Their use can help boost air quality.

All forced air HVAC heating and cooling systems need adequate airflow to function correctly – air filters help facilitate this. When you change furnace filter units, the clean filter works to help the system stay balanced and avoid static pressure buildup.

What Happens When You Don’t Replace Furnace Filters?

When you fail to change your furnace filter, a number of issues may arise in your home. You need to keep filter replacement on your to-do list and change a furnace filter regularly to avoid problems such as:

  • Higher energy consumption. Dirty air filters are no longer effective for the removal of airborne contaminants, so these particles are allowed to pass into the furnace where they settle out of the air supply onto components. Dust and grime hinder performance, forcing the furnace to use more energy when heating your home. Increasing energy bills are a warning sign that your furnace is in need of filter replacement.

  • Poor heating performance. Airflow restriction due to a dirty filter prevents the furnace from correctly heating your home. The equipment uses more energy as it attempts to circulate heat in spite of the resistance caused by the old filter, but even so, the system typically struggles to provide proper heating across all the home living areas. Occupants of the home will notice cold spots and may find some areas are harder to heat, like those furthest away from the furnace.

  • Higher breakdown risk. Dirt accumulation on top system stress due to airflow restrictions creates a higher likelihood of furnace breakdowns. HVAC components may be damaged when the furnace continues to operate with a dirty filter in place. Poor airflow causes internal temperatures to rise inside the furnace and leads to overheating that shuts down the system and causes harm to critical parts such as the heat exchanger.

  • Shorter system lifespan. The increased stress, wear and tear a furnace experiences when operated with a dirty filter not only causes more breakdowns, but it is likely to cut years from the furnace’s expected service life. Furnace replacement will be needed more frequently, resulting in significant expenses that could have been avoided with proper filter maintenance.

  • Poor indoor air quality. When the dirty filter is unable to remove contaminants from the air supply, these particles cycle back into your home. Living areas are filled with higher concentrations of pollutants which may cause comfort and health issues among occupants. These particles eventually come to settle on surfaces, dirtying up your home.

When to Remove and Replace Air Filters

How do you know when it’s time to change your filter? The amount of time between changing will vary from one home to the next – the filter’s type, thickness size, and MERV rating along with the air quality and heating usage of the home impact how often a new one is needed. If you have a larger household, indoor pets, family members who are sensitive to allergens, or smoke indoors, you’ll find the filter becomes clogged with contaminants faster than it would in a home where these factors are not present and you need to change your filter more frequently.

Filter manufacturers typically offer a recommendation as to how often you should change a furnace filter, which may be anywhere from every one month, every six months, or once every year. These recommendations are a guideline – you need to check your filter often to know how often you need to be changing it.

  • MERV 1 to 4 filters should be changed every month.
  • MERV 5 to 8 filters should be changed about every three months.
  • MERV 9 to 11 filters should be changed approximately every six months.
  • MERV 12 to 16 filters should be replaced every nine months to one year.

During the winter months, HVAC units run for much of the day. Increased system usage during the cold means the filter fills faster than during periods of milder temperatures, so the time between filter changing varies by the season. For this reason, it’s a good idea to remove and check the filter every month to know its condition and if it’s time to replace.

Which Way Does the Furnace Filter Go?

Changing filters is an easy maintenance step that most homeowners find they’re able to do on their own. When you change a furnace filter, just remove the old one and replace it with a new one.

However, not just any old filter will do – you need to know the right size. In the hardware store’s filter aisle, you’ll find there are a multitude of different-size filters available. Before you buy a replacement, check the markings on the existing filter or your furnace owner’s manual to know the correct option. If you use a filter of a different size, it won’t work correctly. The filter won’t fit properly in the filter cabinet, which allows air to pass by unfiltered, and the filter could fall, causing a blockage in the furnace.

Step-by-step instructions to change furnace filter disposables are as follows:

  1. Locate the air filter compartment on your furnace or air handler – in the average system, furnace filters are located on the return side, where air enters the unit for heating. There may be a cover which you need to remove to access the filter.
  2. Remove the existing furnace filter and dispose or clean it (for reusable filters only). Disposable filters are typically not recyclable, though some manufacturers may offer a mail-in recycling option.
  3. Remove packaging from the new disposable furnace filter and place it into the filter compartment. The direction of the filter’s orientation matters, as a new filter in the wrong direction can impede airflow. Disposable filters usually have an arrow printed on the frame to indicate proper direction. Make sure the direction you insert the filter matches the arrow.

 If you use a washable, reusable air filter, you need to wash it before replacement. Lay the filter flat with the dirt and dust facing up. Vacuum the filter to remove dirt and debris as best as you can. Next, rinse the filter with water to remove remaining debris, using your hands or a soft brush to loosen them as needed – do not use soap or detergent to clean the filter. Let the filter dry completely before reinserting it in the compartment in the proper direction.

4. Replace the filter compartment access panel, if applicable.

Make Furnace Maintenance a Priority This Season

Filter maintenance is critical to the efficient performance of your furnace or heating system throughout the winter season. The tips above explain why it’s so important to keep up with this routine step. If you have questions about furnace filters for your heating unit, require help to change a furnace filter, or wish to purchase furnace filters for replacement, contact Williams Comfort Air today.

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