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HVAC Filters 101

What is an air filter?

An air filter is an essential, simple device that consists of super small tightly packed fibers that help trap and remove contaminants and impurities from your air (think: dust, pollen, mold, etc.). They are used in all heat and air conditioning syst

Do I need an air filter?

All HVAC systems require an air filter to function. While cheaper fiberglass filters only protect your HVAC from dust and debris, Windmill filters are also specialized in cleaning microscopic particles from the air you breathe at home. So if you're i

How does an air filter work?

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 co

What are the benefits of an air filter?

Air Filters have 3 primary benefits. Windmill Filters:. Air Filters have 3 primary benefits:. Health Benefits. Air filters clean the air you breathe at home, delivering many health benefits to you and your loved ones. Clean air isn't just good decrea

Why do I need to change my air filter?

Eventually, after about 2-3 months, the air filter will clog with so much gunk (after capturing so many particles and contaminants) that it must be replaced in order to maintain proper airflow in your HVAC unit. Just think about how hard it is to bre

When should I change my air filter?

While the general rule of thumb is to replace your filter every 2-3 months, every home is a sanctuary, and not all sanctuaries are alike. You may have pets, suffer from allergies, have kids kicking up dust, or cook like a pro chef! Because the life o

Where is the air filter in my home?

If you have central air, your air filter is most commonly found in. Occasionally, you may also find your filter in a vent in your floor. Air filters are most commonly found in one of two locations:. 1) In a wall OR ceiling behind a large grate/vent.

Can I use a HEPA filter in my furnace?

We wouldn't recommend it. HEPA filters are able to filter out even the very smallest particles. Because of that though, it's hard for air to pass through HEPA filters, which doesn't make them a good option for your whole-home HVAC system. By not allo

What is MERV? What about MFR and FPR?

MERV, MFR, and FPR, are reporting standards for filter efficiencies (or performance levels). Basically, the higher the rating, the more the device filters out. Just keep in mind that the more you try to filter, the harder it is for air to pass throug

How does where you live affect what air filter I should use?

When thinking about what air filter you should use, humidity levels (which impact mold and mildew growth), seasonal patterns (like allergies or wildfires) and your local AQI (or Air Quality Index) all have a huge impact on how the air outside affects

Why are there different size air filters?

Just when you thought air filters weren't confusing enough, it turns out each filter actually has two sizes! "Actual" and "nominal" sizes have entered the chat. Actual sizes are the exact dimensions of the filter (i.e. if you were to measure it with

How do I know my air filter size?

You can find your air filter size in three ways (just remember to turn off your HVAC before doing any of these 😄):. Check the frame of your old filterMost common. The size should be printed on it. If there are two measurements, use the rounded up fi

What is the difference between fiberglass and pleated air filters?

Fiberglass filters serve only one purpose, and that is to protect your furnace or air conditioning system from particulate build up. Pleated filters (known for their accordion look) not only protect your system from this gunk, but they also significa

What is the difference between an Air Filter and an Air Purifier?

The key difference is that an air purifier is a standalone device used to clean the air of a single, specific room, whereas an air filter is instead a necessary component of your HVAC system that is used to protect your unit and clean the air of your