How Often Do You Need to Change Air Purifier Filters?

air purifier filters



Purchasing a quality air purifier is a serious investment. Making that investment means you care about the air you, your family, your friends, and your clients breathe. But keeping your air clean isn’t a set it and forget it process, as you need to regularly change your air purifier filters. 

Read on to learn why it’s important to replace your air purifier filter, how often you should replace your filter, and the factors that can affect timing. 

Why You Need to Replace Air Purifier Filters

Every time you turn on your air purifier, the unit begins to scrub the air of air pollutants, volatile organic compounds (VOCs), bacteria and viruses, smoke, mold and mildew, pet dander, and more. 

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These various microscopic particles get caught in the filters of the air purifier, which hold onto them and prevent them from entering your lungs, similar to the way a furnace filter traps airborne contaminants. 

Consider that furnace filter. When you don’t change the filter regularly, dust, mold spores, bacteria, allergens, and more build up in the filter, making it difficult for air to pass through easily. This means your system has to work that much harder, leading to overheating. Overheating can cause serious damage to your system, and if left long enough, it could result in costly repairs or the complete replacement of your furnace. 

Over time, the filters in an air purifier get clogged too. A filter saturated with harmful or irritating particles slows down the cleaning process, forcing the air purifier to work harder, thereby putting more strain on the unit. The more strain the air purifier is under, the more likely it is to become damaged.  

Without regular filter replacement, your air quality will decline, and in extreme cases, you may damage your unit. These repairs are much more costly and inconvenient than simply changing the filters on schedule.

Replacing air purifier filters regularly prolongs the lifespan of the unit and ensures that it continues to work at optimal efficiency. 


How Many Filters Are in an Air Purifier?

Depending on your unit, the air purifier could come with a few different filters or components that each serve a unique purpose. Our AllerAir purifiers come with a pre-filter, an activated carbon filter, and a large Medical Grade True HEPA filter or a Super HEPA filter. 

What Do Each of the Filters Do?

Pre-filter: Captures large particles and prevents the main filters from clogging.


HEPA or Super HEPA Filter: Removes fine airborne particulate matter.

Activated Carbon Filter: Removes chemicals, gases, and odors. 

UV-C Bulb: Neutralizes biological contaminants.

Contaminated air is drawn through the bottom of the air purifier, where it first goes through the pre-filter, then through the activated carbon filter, then through the Medical Grade True HEPA filter or Super HEPA filter. After the air passes through each of these filters, it is vented out through the top of the unit. A UV-C light can also be added to any of our air purifiers. The UV light kills viruses, bacteria, germs, and mold, adding a fourth stage of air filtration. 

Each of these filters is built to last, but not forever. To keep your unit performing optimally, it will be necessary to periodically change each of these air purifier components. 

Factors that Could Affect Timing

Depending on the environment you use the air purifier in (e.g., commercial vs. residential), it may not be necessary to change your filters as frequently. 

Consider the air quality in your home or office. Are you in an area that suffers from frequent wildfires? Do you live next to a busy road where cars emit a great deal of exhaust? Do you smoke inside your home? Do you live with pets? How often do you use the air purifier? Only occasionally, or do you have it running all of the time?

All of these factors affect the timing of when you need to change your air purifier filters. In a nutshell, the more you use the air purifier and the harder it has to work to scrub the air, the more often you will need to replace the filters. 

How Often Should You Replace Filters?

In general, we recommend the following replacement schedule, though it could vary depending on your environment’s air quality and how many people pass through your space. 


Pre-filter: Change this every three months.

Activated Carbon Filter: Change this every two – five years.

HEPA or Super HEPA Filter: Change this every two – three years. 

UV Light: Change the UV-C bulb annually. 

That said, if you are using the air purifier in a commercial environment, it’s best to change the activated carbon filter and HEPA or Super HEPA filter every year, which you can do at the same time to ensure you remember to do both. 

Video: How to Change AllerAir Air Purifier Filters


How Do You Know it’s Time to Change a Filter?

While sticking to your air purifier’s recommended replacement schedule is a great way to keep on top of changing the filters in your air purifier, it’s also important to rely on your own discretion. If you feel like the air quality in your home or office is declining, it may be necessary to change your filters more regularly. 

Replace your air purifier filters if:

  • You notice a bad odor.
  • You or the people you share your space with are experiencing more severe allergy or asthma symptoms.
  • Your home or office is dustier than usual.
  • The filter looks grey, indicating a considerable amount of dust and dirt buildup.
  • You notice more pet dander circulating in the air.
  • The area where you live is experiencing significant and prolonged wildfires.


A quality, Canadian-made air purifier is a big investment that needs to be taken care of. To reap the full benefits of your air purifier, it’s best to replace your filters on schedule or as soon as you notice a decline in the air quality of your home or office.

Contact Intelligent Air for Specific Questions About Filter Replacement

While we generally recommend changing your air purifier filters every one to two years, every environment is different. If you have specific questions about our filters or when you should change your filters, please don’t hesitate to reach out to us. 

You can order replacement filters, parts, and accessories directly from Intelligent Air.

Intelligent Air is a Canadian company proudly based in Waterloo, Ontario. We specialize in AllerAir Air Purifiers that target fire particulate matter, viruses, bacteria, and other harmful air pollutants. 


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Every purifier we offer is made in Canada with Canadian parts, including a metal housing and a 10 year warranty. We wouldn’t sell a product we didn’t believe in ourselves, so you can count on our air purifiers to include a HEPA or Super HEPA filter, deep-bed activated carbon, and a quality germicidal UV bulb.


To learn more about what air purification system is right for your home or business, contact our team today

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