Have you noticed your home smelling musty or feeling lukewarm when using your furnace? If you haven’t changed your filter in a while, you might wonder, “Do furnace filters improve air quality?” The answer is yes, and keep reading to discover how!

When you need furnace maintenance, contact Leith Heating & Cooling, the best professional furnace company in Elgin. We’ll restore your heat and comfort to your home. Call us at 847-534-8686 today.

Types of Furnace Filters

In general, your type of filter falls under one of three categories.

HEPA Filters

These filters offer the highest level of filtration and last the longest without maintenance. They make the best option for houses with smokers or pets or for those with allergies or respiratory problems. You should check the HEPA filter every six months, but they can last up to a year.

Disposable Pleated

Disposable filters offer the cheapest option, especially if you can make them last for their maximum life expectancy. With this type, you’ll require a new filter every 90 days. Waiting longer causes a buildup of dust and other allergens that can harm your health.


The benefit of washable filters is they don’t require a new purchase every three months, though they cost more than disposable filters. Wash them at least every 90 days. If the filter becomes damaged, you’ll require a replacement.

What Affects How Often I Replace My Filter?

While 90 days is standard for replacing or cleaning your filters, certain factors can increase the frequency you should check them. To increase the life expectancy of your filters, avoid smoking indoors and dust and vacuum your home often.

Air Quality

Your home’s natural air quality could require you to replace your filter more frequently. If you smoke, have pets that shed, or open your windows in a smog-filled city, check your filter every month for accumulated dirt.

Frequency of Use

If you run your furnace day and night, your air filter won’t last as long. To ensure you get the maximum life expectancy out of your filter and keep your energy bills low, only run your furnace as needed.


Even among similar types of filters, different brands can have various life expectancies. If your furnace uses a pre-filter, check it every month to ensure your primary filter stays clean and lasts longer.

How To Tell Your Filter Needs Replacing

Look for these common signs you need to replace or clean your filter:

  • The filter looks grey or black.
  • You notice more dust and dirt around your house than normal.
  • Your allergies or asthma seem worse than usual.
  • Your house smells stale, or you smell musty odors, pet dander, or smoke.

When in doubt, call Leith Heating & Cooling to check, clean, and replace your air filter.

The Benefits of Replacing Your Air Filter Frequently

When you replace or clean your air filter promptly, you’ll experience five benefits that keep you living in comfort.

1. Maintain Healthy Air Quality

Do furnace filters improve air quality? The answer is yes! In fact, that’s the biggest benefit.

Living in your home produces several types of indoor air pollution. These airborne particles include pet dander, mold spores, allergens, dust, and viruses and bacteria from your family. When your filter accumulates dust, it can prevent new pollutants from filtering out and can even worsen your air quality by releasing previously stored particles.

Poor air quality can also decrease the furnace’s airflow, allowing moisture to settle and mold and mildew to flourish. This can cause health concerns and property damage.

If you want the best air quality possible, buy filters with the highest Minimum Efficiency Reporting Value (MERV). These values range from one to 12, and the higher numbers filter out more contaminants. Also, confirm you know which type of filter works best for your furnace.

2. Extend Life Expectancy

Your furnace can last up to 20 years when you care for it. Regularly replacing the air filter is part of the maintenance.

When your air filter accumulates dirt, it forces the furnace to run harder to produce the same effect. The harder your furnace works, the faster it wears out and requires replacement.

A dirty air filter can also cause your furnace to cycle on and off frequently or overheat, which can cause permanent damage. To prevent replacing your furnace before necessary, keep a close eye on your filter!

3. Maintain Low Energy Costs

In addition to reducing your furnace’s life expectancy, when your furnace works harder, it reduces your energy efficiency. Because it needs to use more fuel to achieve the same temperature, you’ll end up paying more for your gas or electricity. In some cases, this can cause a severe spike in your monthly energy costs.

While you may spend a nominal amount on a new filter every one to three months, that money pales in comparison to what you’d spend on higher energy bills. Experts estimate you can save between five and 15% of your monthly energy bill by keeping your filter clean.

4. Increases Safety

While serious complications are rare, don’t you want to ensure your family stays 100% safe? The most common risk arises when the dirty air filter causes the furnace to overheat and break down completely. If this happens during the cold winter months, you could suffer extreme cold.

5. Maintains Consistent Temperature

Your furnace should heat every room in your house evenly. When your air filter clogs, the reduced airflow means your home heats unevenly. You may notice some rooms become extremely hot while others are left completely unheated.

Regularly changing your filter ensures every room in your home or business provides the same level of comfort and safety.

Call Leith Heating & Cooling for All Your Furnace Needs

Do furnace filters improve air quality? Yes, and they serve several important functions! Whether you need to fix your furnace gas valve or replace your air filter, Leith Heating & Cooling can handle it all.

Our certified technicians can’t wait to help you. Call us at 847-534-8686 to schedule an appointment today.

company icon