# Windmill Filters

> Public Help Center articles for Windmill Filters.

Use these links as concise, text-first sources for customer-facing support policies and FAQs.

Each linked article is the Markdown representation of the public Help Center article URL with `.md` appended.

## Articles

- [What is an air filter?](https://support.windmillfilters.com/en-US/what-is-an-air-filter-183209.md): An air filter is an essential, low-effort device that is built as a frame and holds within it a screen of extremely small and tightly packed fibers. They are used in all heat and air conditioning systems and their primary purpose is to trap and
- [What heating or air conditioning (HVAC) systems are Windmill Filters for?](https://support.windmillfilters.com/en-US/what-hvac-systems-are-windmill-filters-for-183210.md): Windmill Filters are for central air HVAC systems or for any heat or air conditioning systems that support our sizes. Click here to see our list of sizes
- [Do I need an air filter?](https://support.windmillfilters.com/en-US/do-i-need-an-air-filter-183211.md): All central air 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
- [How does an air filter work?](https://support.windmillfilters.com/en-US/how-does-an-air-filter-work-183212.md): 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
- [What are the benefits of an air filter?](https://support.windmillfilters.com/en-US/what-are-the-benefits-of-an-air-filter-183213.md): 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?](https://support.windmillfilters.com/en-US/why-do-i-need-to-change-my-air-filter-183214.md): 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?](https://support.windmillfilters.com/en-US/when-should-i-change-my-air-filter-183215.md): 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?](https://support.windmillfilters.com/en-US/where-is-the-air-filter-in-my-home-183216.md): Short answer: If you have central air, your air filter is most commonly found in A) a wall OR ceiling behind a large grate/vent or B) next to your furnace or air handler, which is usually found in a basement, attic, or utility closet Long Answer: Air
- [Can I use a HEPA filter in my furnace?](https://support.windmillfilters.com/en-US/can-i-use-a-hepa-filter-in-my-furnace-183224.md): 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
- [What is MERV? What about MFR and FPR?](https://support.windmillfilters.com/en-US/what-is-merv-what-about-mfr-and-fpr-183217.md): Short Answer: MERV, MFR, and FPR, are reporting standards for filter efficiencies. 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 through the
- [How does where you live affect what air filter I should use?](https://support.windmillfilters.com/en-US/how-does-where-you-live-affect-what-air-filter-i-should-use-183218.md): When thinking about what air filter you should use, seasonal patterns (like allergies or wildfires) and your local AQI (or Air Quality Index) have a huge impact on how the air outside affects you at home. Additionally, according to the EPA
- [Why are there different size air filters?](https://support.windmillfilters.com/en-US/why-are-there-different-size-air-filters-183219.md): Short answer: Actual sizes are the exact dimensions of the filter (i.e. if you were to measure it with a tape measure), while nominal sizes are the filter dimensions rounded-UP. Long answer: Just when you thought air filters weren�t confusing enough
- [How do I know my air filter size?](https://support.windmillfilters.com/en-US/how-do-i-know-my-air-filter-size-195679.md): You can find your air filter size in three ways: Check the frame of your old filter (most common). The size should be printed on it. If there are two measurements, use the rounded up figures as your reference. Measure your old filter (with a tape
- [What is the difference between fiberglass and pleated air filters?](https://support.windmillfilters.com/en-US/what-is-the-difference-between-fiberglass-and-pleated-air-filters-183221.md): Short answer: Fiberglass filters serve only one purpose, and that is to protect your furnace or air conditioning system from particulate build up. Pleated filters not only also protect your system from this gunk, but they also significantly improve
- [What is the difference between an Air Filter and an Air Purifier?](https://support.windmillfilters.com/en-US/what-is-the-difference-between-an-air-filter-and-an-air-purifier-183237.md): Short answer: The key difference is that an air purifier is a separate 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
- [How do I know my air filter is working?](https://support.windmillfilters.com/en-US/how-do-i-know-my-air-filter-is-working-183222.md): Most particles that your air filter is capturing are too small for us to see. So even if your filter �looks� clean, it�s more likely that it is full of microscopic contaminants. That said, with time, your air filter will build up a layer of gunk
- [Do I need to be concerned about airflow?](https://support.windmillfilters.com/en-US/do-i-need-to-be-concerned-about-airflow-183223.md): It's a great thought! But not with our filters :). All Windmill Filters have been tested and approved for residential use. The trick though is to make sure you replace your filter on time. A clogged air filter (i.e. one that is not replaced on time)
- [Should I layer my 1" filters?](https://support.windmillfilters.com/en-US/should-i-layer-my-1%22-filters-183225.md): No. 1" air filters were not built to be stacked and doing so significantly reduces airflow.
- [Can you place a 1" filter in my larger 2", 3", or 4" wide slot?](https://support.windmillfilters.com/en-US/can-you-place-a-1%22-filter-in-my-larger-2%22-3%22-or-4%22-wide-slot-183226.md): Even though a 1" filter fits, we would not recommend using one as your HVAC unit was built to function with a wider filter. However, if you are looking for a larger filter, let us know by filling out this quick form. We are a small business trying to
- [What is the difference between the Windmill filters?](https://support.windmillfilters.com/en-US/what-is-the-difference-between-the-windmill-filters-183228.md): Our filters vary based on how much they filter out. A side-by-side comparison of our filters can be found here (link to �Our Filters'' page). And if you need any help filtering out the best filter for you, take our quiz! We�re here to take care of
- [Will Windmill Filters help my allergies?](https://support.windmillfilters.com/en-US/will-windmill-filters-help-my-allergies-183229.md): Yes! All of our filters are capable of capturing particles like pollen and allergens. If you need help finding the best filter for you, take our quiz!
- [Are Windmill Filters good for pet owners?](https://support.windmillfilters.com/en-US/are-windmill-filters-good-for-pet-owners-183230.md): They sure are! Our Preferred and Medical filters are capable of capturing particles like fur, dander, and pet allergens. If you need help finding the best filter for you, take our quiz!
- [Which Windmill filter is best for me?](https://support.windmillfilters.com/en-US/which-windmill-filter-is-best-for-me-183231.md): That totally depends on you and the air in your home! Learn more by visiting our filters page or take our quiz to find out right away which filter is best for you.
- [What particles do Windmill filters capture?](https://support.windmillfilters.com/en-US/what-particles-do-windmill-filters-capture-183232.md): Windmill Filters are able to filter out certain particles based on how tight their fibers are. All of our products are designed to capture contaminants like dust, pollen, and mold, and some of our more advanced filters can even block dander, pollutan
- [What sizes do you offer?](https://support.windmillfilters.com/en-US/what-sizes-do-you-offer-183233.md): We currently offer 12 sizes of 1" inch filters:. If your size isn't available, click here to tell us what size you need and you'll be notified (with a coupon!) when your size is ready. We are a small business trying to grow and plan to roll out many
- [Why does Windmill ship in bulk?](https://support.windmillfilters.com/en-US/why-does-windmill-ship-in-bulk-183234.md): We ship in bulk (annual packs) to pass the savings directly to you and help decrease our carbon footprint. Many filter companies ship a filter to you every time you need to replace it. We'll just text you instead. This not only means fewer deliveries
- [Can I buy just 1 filter?](https://support.windmillfilters.com/en-US/can-i-buy-just-1-filter-183235.md): We currently only offer filters in packs of 4 or 6 (better for your wallet and the planet!). We are a growing small business and plan to roll out more buying options in the near future.
- [How does the quiz work?](https://support.windmillfilters.com/en-US/how-does-the-quiz-work-183236.md): Buying filters can be confusing - so many options and weird words. We built our quiz to make it simpler. We’ll ask you questions about the makeup of the air in your home and, based on that information, we’ll recommend the best type of air filter and
- [Are Windmill Filters recyclable?](https://support.windmillfilters.com/en-US/are-windmill-filters-recyclable-183238.md): Windmill Filters are meant to be disposed of because of the various particulates and contaminants they capture. In order to help offset the carbon footprint of our product we have partnered with Ecocart (learn more here).
- [How do I store my filters?](https://support.windmillfilters.com/en-US/how-do-i-store-my-filters-183239.md): We would recommend storing your filters in the box that they arrived in. However, if you prefer to keep the filters only instead, you are good to do so. They arrived individually wrapped so you don�t have to worry about them getting dirty while
- [Can I wash and reuse my filters?](https://support.windmillfilters.com/en-US/can-i-wash-and-reuse-my-filters-183240.md): Windmill Filters are not washable and should be disposed of and replaced after use. Trying to wash and reuse an old Windmill filter can disperse moisture into your HVAC unit and ducts, which significantly increases the risk of mold spreading in your
- [How do I dispose of my filters?](https://support.windmillfilters.com/en-US/how-do-i-dispose-of-my-filters-183241.md): Because your dirty filter will be covered in dust, gunk, and other contaminants that you don�t want to be inhaling or messing with, we recommend having a trash bag ready when you�re replacing it, throwing it right in there, and disposing of it in
- [How do I change/install my air filter?](https://support.windmillfilters.com/en-US/how-to-install-air-filter-183265.md): How do we customize these instructions with our Text Reminders and QR code? (1) Turn off your HVAC system so that air doesn't keep blowing while you're there changing your filter. (2) Open the vent or slot where your air filter is located. If you
- [What are the product details?](https://support.windmillfilters.com/en-US/what-are-the-product-details-183245.md): Windmill filters are made by the #1 filter media manufacturer in the world.
- [What makes Windmill filters unique?](https://support.windmillfilters.com/en-US/what-makes-windmill-filters-unique-183246.md): We started Windmill filters to make buying and replacing your home air filters easier (and a little less boring).
- [Where are Windmill Filters made?](https://support.windmillfilters.com/en-US/where-are-windmill-filters-made-193224.md): Windmill Filters are proudly made in the USA by the #1 filter media manufacturer in the world.
- [What is your cancellation policy?](https://support.windmillfilters.com/en-US/what-is-your-cancellation-policy-183253.md): We know plans change. You can cancel an order up until receiving your shipping confirmation email. If your order has already been shipped, email us at support@windmillfilters.com to set up a return.
- [What is your return policy?](https://support.windmillfilters.com/en-US/what-is-your-return-policy-183254.md): We're pretty sure you'll love your new filters, but if for whatever reason you don't, we have a free 30-day, no-questions-asked return policy. Just email us at support@windmillfilters.com and we'll send you a prepaid return shipping label with instru
- [What if I bought the wrong size? What is your exchange policy?](https://support.windmillfilters.com/en-US/what-if-i-bought-the-wrong-size-what-is-your-exchange-policy-183257.md): Wrong size, awkward fit? No prob. Reach out to our support team at support@windmillfilters.com to set up a return and feel free to reorder the correct sized filters at any time!. Need help finding your size? Click here.
- [How do I contact customer support?](https://support.windmillfilters.com/en-US/how-do-i-contact-customer-support-183261.md): Need help? Send us a message at support@windmillfilters.com or feel free to chat with us during our business hours!
- [When will my filters arrive?](https://support.windmillfilters.com/en-US/when-will-my-filters-arrive-183263.md): Once placed, your order will typically ship from our warehouse within 1-2 business days. After that, you'll receive a tracking number from one of our carriers. Please note that your tracking number will work once the carrier (FedEx, UPS, or USPS) sca
- [What is the status of my order?](https://support.windmillfilters.com/en-US/what-is-the-status-of-my-order-183264.md): Looking for an ETA? You can log into your Windmill account here to check on your order status, track your shipment, or manage your auto-refill(s). If you have any trouble, don’t hesitate to contact our support team via the chat widget or at support@w
- [How do your annual auto-refills work?](https://support.windmillfilters.com/en-US/how-do-your-annual-auto-refills-work-195553.md): Looking to save money, decrease your carbon footprint, never forget a filter change again? You’ve come to the right place. Here’s how the annual auto-refills work:. Once the year is up and you’ve used all of your filters from the bulk pack, we will s
- [How does Windmill reduce its carbon footprint?](https://support.windmillfilters.com/en-US/how-does-windmill-reduce-its-carbon-footprint-183227.md): Every time you buy a pack of Windmill filters, we�ll automatically purchase verified emissions reductions, more commonly known as �offsets,� on your behalf (at no additional cost to you). These offsets support environmental and sustainability
- [**Filter material sustainability](https://support.windmillfilters.com/en-US/filter-material-sustainability-183247.md): And anything we get from Freudenberg
- [How do I sign up for text reminders?](https://support.windmillfilters.com/en-US/how-do-i-sign-up-for-text-reminders-183242.md): You are actually signed up automatically after checkout! However, if you did not receive a text message at least 24 hours after you placed your order, please reach out to customer service (by either emailing us at support@windmillfilters.com or by ch
- [How do text reminders work?](https://support.windmillfilters.com/en-US/how-do-text-reminders-work-183244.md): Remembering when to replace your filter is, well… another to-do on the already 1000+ home chores list to stay on top of. Let us handle this one. We’ll text you every time you need to change your air filter so that you don’t have to think about it. We