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How does an air filter work?Updated 3 months ago

Short Answer: 

When you turn on your AC, air is sucked in through your vents and then passes through the air filter, which captures unwanted particles and contaminants. That now filtered air is then heated or cooled, and is then pushed back out of other vents as comfortable and clean air. The more times this process repeats, the cleaner your air gets. Eventually, after about 2-3 months, the air filter will clog with gunk (after capturing so many particles) that it must be replaced in order to maintain proper airflow in your HVAC unit. 

Long Answer: 

An air filter works just like all of the other filters that we are familiar with in our daily lives. Colanders, sieves, tea bags, masks, water filters, coffee filters, lint catchers in dryers, and even nose hair 😅 . An air filter blocks and captures unwanted particles from the air that moves through it. 

Air being cleaned as it passes through a filterHere is how an air filter works specifically in your central air: 

  • When you turn on your heat or AC, air is sucked in through vents 
  • That air passes through ducts until it eventually meets the heart of the HVAC system, where it is "treated" (i.e. heated or cooled) 
  • That hot or cold air is then pushed back into your home through different vents as more comfortable air 

During this process, air will always, at some point, pass through the air filter. This means that the air that is being pushed back into your home is not only now hot or cold, it is also cleaned and filtered. 

The contaminants captured by the filter normally include dust and lint, but Windmill filters are even capable of blocking mold, pollen, dander, pollutants, bacteria, and some viruses (our different filters are pictured below). Additionally, our filter's electrostatic charge actually attracts particles to make them easier to capture and its fibers are anti-microbial (which prevents any sort of unwanted growth).  The more times the air HVAC cycle repeats, the cleaner your home air gets. 

Fibers tighten as MERV rating increasesEventually, after usually 2-3 months, an air filter must be replaced. As air continuously circulates in your home, your air filter, which has been working behind the scenes constantly capturing particles, will clog like a stuffy nose, and airflow will be restricted. In order to avoid increasing energy costs and "suffocating" your HVAC system, it is best to replace your filter on time and on a regular basis.

Clean filter, Dirty filter (before and after)

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