Air filters are a central but often underappreciated part of an HVAC system. They filter out pollen and dust that would otherwise circulate through the home and lower indoor air quality. This includes irritating particles invisible to the naked eye.

If you could see what is floating around in your home, you would be shocked. Dirt, dust, mold and fungal spores, pet dander, and fabric fibers are robbing our homes of fresh, clean air. 

This is especially true when houses are buttoned down for the winter after having had windows open throughout the spring and summer months.

Air filters also provide a first line of defense against larger objects — such as bits of loose insulation — from being pulled into the system where they could cause damage or present a fire risk. 

You may have heard HVAC filters should be changed every 90 days. But, you lead a busy life, and it’s easy to forget this task. 

If your replacement schedule is spotty, to say the least, and you’ve not experienced any consequences, you may begin to think it’s okay to not change your filter. 

This is far from the truth. Once you fully understand what happens when you forget to change your filter, you’ll be more inclined to make consistent replacement a priority. 

Clogged HVAC Filters Can Lead To:

Health Concerns

The air quality of your home plays a big part in your overall health. If you’re not changing the air filters in the house, dust and allergens can circulate throughout your home, and you’re increasing the risk of your household getting sick. Family members will be more susceptible to colds and allergies can be miserable.

HVAC Failure

Clogged air filters are the number one cause of system failure. An HVAC system has to work hard to pull air through a clogged filter. 

This continuous strain on the unit can cause it to break, requiring you to pay for expensive repairs or needing a brand new system.

High Energy Bills

When a filter is clogged, your system has to work harder to pull air through to cool or heat the room. This causes it to run for longer periods of time, increasing the energy your home uses. 

Getting that energy bill every month is not fun. With an inefficient air filter, your system uses more energy, and this drives up your bill. The average household spends about $2,200 annually on energy bills, according to The Department of Energy. 

By regularly changing your air filter, you can save from 5-15% on your utility costs. 

Changing Your Air Filter

Generally, most air filter manufacturers and HVAC companies recommend changing your air filter every 90 days, or three months. This may vary based on where your home is located (for example, living in a particularly dusty locale), if you have pets, and/or the age of your system and equipment.

One of the easiest ways to spot an air filter that needs changing is to actually take a look at it. A clean and fresh filter will be mostly white in color but will get darker as it gathers dust and dirt. If your filter looks dark and dirty, it’s time to change it.

Another way to determine if your air filter is dirty is to do the “white sheet test.” This involves hanging a clean white sheet approximately 5 inches away from one of the vents for at least one hour. If the sheet turns gray, you’ve got a filthy air filter. The grayer the sheet, the dirtier the filter.

HVAC units are expensive. Squeeze the most time out of your system by regularly replacing the air filter. In addition to staying on top of filter replacement, you can also extend the life of your HVAC by having an annual inspection by a professional and certified technician.

We Help Homeowners

Flader Plumbing and Heating is uniquely suited to assist you in determining the solution that best fits your home and family’s needs. We’ve been serving your neighbors and our community for over 100 years and 4 generations. 

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Only Flader Plumbing and Heating delivers:

  • The most responsive service. We’re here for you 24/7.
  • Personal attention from certified and licensed technicians.
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  • 100% satisfaction guaranteed.


Flader Plumbing and Heating recommends equipment, models, and brands proven to have the fewest problems and service calls. We specialize in:

Comprehensive Services

Whether you’re concerned about tree-related damage, need a water heater, or your A/C is on its last July, we are knowledgeable and provide expert service. Our professional technicians arrive on time, listen to your concerns, and answer your questions. They will recommend the right solution and deliver as promised.

Flader technicians average 15 years of experience and are EPA certified.

Expert service, quality parts, and satisfaction guaranteed. There is no reason to compromise. Call us at 847-491-6980. 

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Flader thrives on exceeding expectations of our residential and commercial customers.  We deliver cost effective solutions for homeowners and businesses.  Our Service Centers in Evanston and Libertyville are ready to serve.  Call us today at 847-491-6980.

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A long-term commercial customer needed an upgrade on their air quality system.It required two 20-ton and two 10-ton Carrier units mounted on the rooftop, plus piping and custom sheet metal inside their manufacturing center. The Flader Team went skyward with a huge crane to land the units on the rooftop.In just 2½ days, the transformation was completed.Click “See our Work” to view more success stories.

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Evanston Service Center: 3004 Central, Evanston, Il 60201
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