Winix - C909

https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491 I have this one. Works pretty good as far as I can tell. Has a mesh pre-filter, charcoal filter, then a HEPA. Pumps a lot of air if you crank it up. Also have smaller non-hepa in each kids room. Change your AC filter regularly, but stick to MERV8.

I was looking for the best value as well on Black Friday, I ended up going with the Winix Costco deal and called it a day. I bought two of them, they should arrive in a couple days.

Yeah, don't buy Dyson air purifiers - almost all of them do a poor job. Freestanding air purifiers can't overcome architectural barriers such as wall and doors. You at least one per room or area. [Per AHAM's rule of thumb](https://ahamverifide.org/ahams-air-filtration-standards/), Clean Air Delivery Rates (CADRs) should be *at minimum* 2/3 of a room's area (assuming an 8 ft. high ceiling). For wildfire smoke treatment, Smoke CADR should *equal* your room's area, again with an assumption of an 8 ft. ceiling. Therefore we would need the length x width x height of each room/area where you'd like a purifier. Purifiers can be very expensive, especially the powerful and quiet models. If you're a member of Costco, have a look at the **Winix C909**. CADRs are in the low to mid-300s CFM. Price is $199.99. This model has an on/off ionizer. Drawbacks: it's fairly loud on the highest setting "Turbo" (around 60 dBA according to the Decibel X phone app). Winix is more of a mid-grade brand; we've had some reports of whirring, whining, or clicking noises after the 2 year mark. This is usually an issue with bad motor bearings. [Link to the Costco Winix C909 is here](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi-%2526-plasmawave-technology.product.100842491.html). Remember that CADRs apply to the highest setting only. Lower speed/fan settings have lower CADRs. In tandem with freestanding purifiers, you can consider installing an HVAC cabinet air purifier. One example is AprilAire. (Other traditional HVAC equipment makers offer these too, such as Trane, American Standard, Lennox, Carrier, Rheem, etc.) The filters are 4-inches to 5-inches deep, which have greater surface area and lower pressure drops than standard 1-inch deep integrated filters. However, if you want to add a cabinet air purifier, be sure to consult an HVAC technician to do load calculations. Choosing too high a MERV filter rating can overtax your equipment and lead to reduced ventilation. Keep in mind that HVAC cabinet air purifiers do not immediately address particulates *within* each room or area. They're best at preventing recirculation of said pollutants throughout the house (in addition to keeping the blower wheel and evaporator coil cleaner).

Unfortunately that's a low budget for the space's size. You are correct about CADRs; keep in mind those are minimum recommendations. If smoke particles/ash/soot levels are especially heavy, 800 CFM CADRs may not be enough. Usually the best value HEPA purifier is the **Winix C909** at [Costco Canada for $289.99](https://www.costco.ca/winix-c909-4-stage-air-purifier-with-wifi-and-plasmawave-technology.product.4000257649.html). Smoke CADR is 323 CFM. If you need to maintain a strict budget, you could consider the **AirFanta 3Pro**, inspired by a Corsi-Rosenthal box design. It uses proprietary Efficient Particle Air (EPA) E11 filters. [E11 is two filter classes below HEPA H13](https://www.airum.com/frontend/immagini/files/EN%201822-1.PDF). This means E11 is less efficient on a single pass, but allows for greater air flow and CADRs. The top speed's composite CADR is 413 CFM for the CARB Edition. [Price for one unit is $229 Canadian](https://air-fanta.com/products/airfanta-3pro).\* You would need two units running at top speed to meet the minimum CADR. \*I added the 3Pro to my cart and in checkout, selected Canada as the shipping destination to see the adjusted product price. AirFanta is not a big player like Winix, Coway, or Levoit. But their filters did sell out during the southern California wildfires back in January. I assume they're in good standing business-wise.

Hard to say. I don't know how closed off they are or what they look like. How large is the opening to each sectioned "room"? Another consideration may be sound levels. Most purifier brands lowball their top sound levels. I own a Winix C909. Combined Smoke CADRs are 646 CFM. On the highest setting called "Turbo", I used the Decibel X Android app and got a reading of 60 dBA. Using a basic [Decibel Calculator](https://noisetools.net/decibelcalculator), running both at this speed would be 63 dB(A). Three Coway Airmega 150 units give you a combined Smoke CADR of 459 CFM. Again using the Decibel Calculator, the three units would be 53.1 dB(A). CADRs are for the highest speed settings only. I don't think Winix measures CADRs for other speeds/fan settings.

he Coway models you listed would be underpowered for the \~500 sq. ft. space; you'd need \~334 CFM CADRs. CADRs should be *at minimum* 2/3 of a room's area (assuming an 8 ft. ceiling). I would avoid the Coway Airmega 100 in particular. Coway is better quality than almost all other consumer brands on the market, but they're more expensive. Some of their Smoke CADRs are low even on the more expensive models. So you'd need two air purifiers to meet CADRs in that room (e.g., one [Coway Airmega 240](https://cowaymega.ca/products/airmega-240?variant=40263676592170) and a [Coway Airmega 160](https://cowaymega.ca/products/airmega-160)). The only purifier that comes close to all except one particulate CADR and budget is the Winix C909. Drawbacks: it's loud on "Turbo"; using the Decibel X app, my C909 measured 60 dBA. Winix is more mid-grade with some people reporting whirring, whining, or clicking noises after the 2 year mark. This is usually a motor bearings issue. PlasmaWave (the ionizer) generally aids the Pollen CADR. It's possible you could see a drop in this value if it's turned off. Keep in mind CADRs are for the highest speed setting only. Lower speeds have lower CADRs. **Winix C909** * Dust CADR: 336 CFM * Pollen CADR: 384 CFM * Smoke CADR: 323 CFM * Price: [$289.99 CAD at Costco.com only](https://www.costco.ca/winix-c909-4-stage-air-purifier-with-wifi-and-plasmawave-technology.product.4000257649.html) EDITED: I glossed over your post and didn't see the "Canada" bit. I've corrected links to their Canadian countertparts.

Freestanding air purifiers can't overcome walls and doors. You need one for each room or area. **Therefore we need each room's length x width x height to calculate Clean Air Delivery Rates (CADRs).** As for your questions: 1. Winix is good, but not the best. I'd generally say Coway is the best in terms of quality for consumer-grade units. 2. PlasmaWave is Winix's name for their bipolar ion generator. It can be turned on or off. PlasmaWave (in practice) seems to enhance Pollen CADR. I believe Levoit's PlasmaPro is also generates positive and negative ions. 3. HEPA vs. "True" HEPA is mostly marketing. What *is* important is listing the appropriate standard, the filter class (where applicable, like H13 or H14), and the filtration efficiency % at a particular particle size or sizes. 4. DIY Corsi-Rosenthal boxes can work very well, which typically use MERV 13 furnace filters. MERV 13 is a lower filtration efficiency than HEPA, meaning it captures fewer particles of certain sizes on a single pass. But... since MERV 13 is less restrictive, it can achieve more passes through the filter media faster which can result in higher CADRs. (Assuming sufficient airflow.) If you wanted to build a C-R box, I would recommend doing so with PC fans. Drawback: most C-R box configurations do not specify fine mesh pre-filters. Without these, the MERV filter media can clog sooner with coarse particulates such as visible dust and hair. 5. "Level of filter": I assume you mean filtration efficiency of a mechanical filter. Mold, fungus, pollen, and viruses are bioaerosols. They can be captured with HEPA, EPA, or certain MERV filters (generally MERV 13 and higher). EPA and MERV 13 filters are a lower filtration efficiency than HEPA, so it will allow more particles through on a single pass. But EPA and MERV 13 can achieve more filter passes and higher CADRs than HEPA with proper airflow for less money. 6. As for secondhand purifiers, that's up to you. Sometimes you can find items that are barely used. But it's also possible purifiers were used in highly polluted environments (e.g., lots of mold or post-fire remediation) or could have bed bugs inside. 7. The blue box looks like an air scrubber. These are meant for more challenging and large environments, e.g. during renovation, fire remediation, or serious mold remediation. Air scrubbers tend to be quite loud.

Are you looking to move one purifier between your bedroom and living room? I would *not* recommend Airpura or AllerAir unless you have a serious gas/vapor/odor/VOCs issue that can't be mitigated with source control or ventilation. In that case, you'd choose one of their heavyweight carbon purifiers. Airpura and AllerAir do make more particulates-focused units, but they don't list particulate Clean Air Delivery Rates (CADRs). They're also known for be very loud. Both are Canadian companies that manufacture largely in Canada and some components in the USA. Levoit is lower quality than IQAir and Coway. The [IQAir Atem X](https://www.iqair.com/us/products/air-purifiers/atem-x) you linked in a comment is high quality and has CADRs in the 400s CFM, but it's very expensive per CADR. As for "True" HEPA, I would say that listing the standard and filtration efficiency at Most Penetrating Particle Size (MPPS) gives you the best idea of performance. There are several HEPA standards. But I don't think there's a significant difference between brands on this front; they will still clean your air. The [Coway Airmega AP-1512HH Mighty](https://cowaymega.com/products/mighty-ap-1512hh) you linked is commonly recommended. It's a good price point and attainable for many. But the Mighty has a few drawbacks like being less energy efficient, somewhat loud, and occasionally people have reported balance issues (e.g., purifier "walking" across a floor). The [Coway Airmega 400](https://cowaymega.com/products/airmega-400) was probably recommended in part because it's "oversized" for your bedroom. Oversizing allows you to run the unit on a quieter setting while hopefully maintaining CADRs. ➡️ If you're expecting one purifier to clean both the living room and bedroom areas, I would also recommend the Coway Airmega 400. The highly upgraded pick would be the [Coway Airmega ProX](https://cowaymega.com/products/airmega-prox). Top Smoke CADR is 568 CFM. It has wheels so you can move it around easily and it shows PM10, PM2.5, and PM1.0 concentrations. Obviously the ProX is fairly big. Keep in mind that CADRs apply to the highest airflow speed/setting *only*. Lower settings have lower CADRs, which reduces cleaning effectiveness. Right now there aren't any fantastic sales directly from Coway. But you can use the discount codes **COWAYMEGA10** or **FORYOU10** for 10% off most items.

I've owned a Winix C909 for a little over a year now. I like it - it's oversized for my 175 sq. ft. office room. Winix is lower quality than Coway generally. Some people have reported whining, whirring, or clicking noises after the 2 year mark, which are usually bad motor bearings. The C909 is fairly loud on the highest setting called "Turbo" (about 60 dBA according to the Decibel X Android app). It's also not energy efficient at 95 W. The C909 also has PlasmaWave, a bipolar ionizer. This can be switched off.

I think the best purifier at Costco now is the Winix C909. CADRs are in the 300s CFM for $199.99. I own one and it's very good value, but it is fairly loud on "Turbo" - around 60 dBA according to the Decibel X Android app. That being said, I think there are other brands with better build quality such as Coway and Alen.

I own a Winix C909 and am very happy with it. But the feedback I've read in this subreddit and seen in reviews is that Coway makes better quality units than Winix. The only Coway purifier quality issues I've seen are rattling/balance issues with the Airmega Mighty AP-1512HH. That and some people complain Coway filters off gas.

Have you read our [sticky post at the top of the subreddit](https://www.reddit.com/r/AirPurifiers/comments/1jxgjwf/sticky_purifiers_and_dust_reduction/) or the [FAQs wiki page](https://www.reddit.com/r/AirPurifiers/wiki/index/faqs/) entries about dust? Air purifiers aren't good at reducing visible dust as it's large and heavy. I would always avoid Shark. It's a low quality brand and we've had multiple reports of the air quality display not working. Coway purifiers are generally the best quality in the consumer-grade market (although they're more expensive). However, you'd have to buy one with the letter *S* appended to the model name. S-letter models have app connectivity. A great value for money is the Winix C909 sold on Costco.com. It has PlasmaWave, a bipolar ionizer that may be turned on or off. The C909 will be fairly loud on the highest setting called "Turbo" - about 60 dBA according to the Decibel X Android app and it's not very energy efficient at 95W. But purifiers need to be sized by room volume - so please list your room's length x width x height. See **Rule 4**.

There's give and take. Winix and Levoit tend to be cheaper when buying the unit and for most filter replacements. You generally have to shell out money for quieter performance while meeting CADRs. For Winix, units have a 2 years warranty, are louder on the highest setting, use more energy per CADR (for flat filter models), and are mid-grade build quality. Some people have issues with bad motor bearings in Winix models after the 2 year mark. I have a Winix C909 from Costco. I don't run it on the highest setting ("Turbo") generally because it's too loud for a 175 sq. ft. office; it uses 95 W on Turbo. Filter replacements are still very cheap from [The Home Depot](https://www.homedepot.com/p/Winix-True-HEPA-4-Filter-Activated-Carbon-Replacement-Filter-A-115115/202034412). Levoit uses the IEST-RP-CC001.6 Recommended Practice (RP) Class H HEPA for (all?) filters and not a HEPA standard. Warranty is 2 years and may be somewhat louder on the highest setting. Build quality is likely mid to above average for the Vital series and EverestAir... I don't know exactly if or when these develop more serious problems or failures.

First, air purifiers aren't very good at reducing visible dust. It's comparatively large and heavy. You can capture more visible dust by oversizing a purifier. If you have high pollution levels, it's recommended to oversize a purifier. I don't know how much you want to pay for a purifier and its filters. That's why we ask for a budget. You're requesting "the best". Quality and cleaning capacity aren't cheap. For the 12' x 20' room, the [Coway Airmega 400](https://cowaymega.com/products/airmega-400) should fit hopefully. The [Airmega 400 Max2 Filter Set](https://cowaymega.com/products/airmega-400-max2-filter-set?variant=33436452323463) is $129 at most, but can be bought for $83 on Amazon. This purifier is for **particulates** (dust, dander, mold spores). However, this model is *not* good for odors. Odors are gases. If you want something cheaper for **particulates only**, have a look at the [Winix C909](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi-%2526-plasmawave-technology.product.100842491.html) sold at Costco.com. You can buy [replacement filters at The Home Depot ($27.99)](https://www.homedepot.com/p/Winix-True-HEPA-4-Filter-Activated-Carbon-Replacement-Filter-A-115115/202034412). Keep the PlasmaWave function turned off. Like I said before, the AllerAir you linked will NOT be good for particulates. AllerAir is for **gases/vapors/odors**. Replacement carbon canisters will be expensive: anywhere from $219 to $336. That is just the nature of high weight activated carbon purifiers. This is why I said you need two different purifiers: one for particulates and one for gases/vapors/odors.

No. PlasmaWave is a bipolar ion generator. From [Winix Switzerland](https://winix.ch/en/blog/plasmawave-technology/): >"These are positive hydrogens (H+) and negative oxygen ions (-O2). Together they form hydroxyl radicals" Certain ionizers have the *potential* to produce ozone. However, Winix's PlasmaWave is [CARB-certified](https://ww2.arb.ca.gov/list-carb-certified-air-cleaning-devices). This means an "ozone emission concentration limit of 0.050 parts per million (50 ppb)". Keep in mind any ozone produced can be *much lower* than 0.050 ppm or 50 ppb limit. Since you have birds, I would definitely keep PlasmaWave off to be safe if you bought this purifier. Hypothetically speaking. The Winix C909 is good for particulates and very bad for odors. It basically has no activated carbon. You would need many pounds of activated carbon for odors, as seen in the AllerAir purifier you linked. But even with many pounds, certain gases/odors may not be well-adsorbed by untreated activated carbon. This can cause the activated carbon to develop a strange smell (sometimes a "sweet" smell, which can be acetaldehyde). We do not know the odors or gases in your space. Therefore I'm wary of recommending the expensive AllerAir purifier you linked (https://allerair.com/products/airmedic-pro-6-plus?variant=42969116174) in case it doesn't work on the odorific gases present or if it causes new odors to manifest.

For a 500 sq. ft. studio, the AHAM 2/3 rule stipulates you need **minimum Clean Air Delivery Rates (CADRs) of 334 CFM**. AHAM 2/3 rule is mentioned the AutoModerator comment. The [Medify Air MA-25](https://medifyair.com/products/medify-ma-25-air-purifier?variant=31541953691715) has a top Smoke CADR of 110 CFM. You need *three* of these units running on the highest airflow speed/setting to get close to min. CADRs. The [Coway Airmega 50](https://cowaymega.com/products/airmega-50) or [Airmega 100](https://cowaymega.com/products/airmega-100) would also be very underpowered. A correction regarding particle size you mentioned: 0.3 microns (or a value/range close to it) is the hardest particle size to capture. This is known otherwise as Most Penetrating Particle Size (MPPS). It *doesn't* mean that smaller particles aren't captured by Winix's HEPA filters. In fact, particles larger *and* smaller than 0.3 microns may be captured with equal or greater effiiciency. [In a blog post, Winix makes the claim—without linking any test reports—of filtration down to 0.003 microns](https://www.winixamerica.com/2021/07/22/ultrafine-particles-the-good-the-bad-and-the-tiny/): >Fortunately, Winix offers a True HEPA filter that goes beyond what can be found on the market today. Every Winix air purifier boasts this industry leading True HEPA filter, which captures 99.99%\* of airborne contaminants down to 0.003 microns in size. \*Based on independent laboratory tests conducted on inanimate particles as small as 0.003 microns. To be fair, Medify Air published a test report on their H13 HEPA [Sub-micron Particulate Filtration Efficiency](https://cdn.shopify.com/s/files/1/0575/1059/2661/files/2023_H13_Filtration_Report_GZHT02739549.pdf) using the ASTM F2100-21 standard‡. As mentioned in Section 9.3, the test measured "initial particle filtration efficiency of materials using monodispersed aerosols containing suspended latex spheres particulates of 0.1μm diameter". Filtration efficiency was 99.9%. The filter test area for each sample was 100 cm^(2) or 15.5 in^(2). ‡[ASTM F2100-21 "Standard Specification for Performance of Materials Used in Medical Face Masks"](https://cdn.standards.iteh.ai/samples/109609/5b29edb6b36f4ac6aa8fb3b36becad6f/ASTM-F2100-21.pdf) is an older version. The most current is now [ASTM F2100-25](https://store.astm.org/f2100-25.html). Even the [Winix C909 ($199.99 at Costco online)](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi-%2526-plasmawave-technology.product.100842491.html) is slightly short on minimum CADRs, where its top Smoke CADR is 323 CFM. This would be on the highest speed or setting called "Turbo". So if I were you, I might go for the Winix C909. It's fairly loud on "Turbo" at 60 dBA (according to the Decibel X Android app) and an energy hog, but it would be closer to min. CADRs.

It will do very little for the dust floating throughout the room, sorry to say. You need incredibly strong air intake and a large filter surface area to significantly reduce dust. I have a Winix C909 purifier with a Dust Clean Air Delivery Rate (CADR) of 336 CFM in a 175 sq. ft. room. This is considered oversized. Even if I run it at top speed for hours on end to achieve the Dust CADR, I can still see airborne dust.

I need the length x width x height of the room(s) where the purifiers will be. This helps us assess particulate Clean Air Delivery Rates (CADRs). If CADRs are too low, you may not be reducing pollutants meaningfully. NB: most common consumer-grade purifier brands—which includes what's sold at Costco—have little capacity to remove gases, vapors, or odors. This is due to very low weights of sorbent media like activated carbon, activated alumina, or synthetic zeolites.

Thanks! Okay, that is big. [Per AHAM](https://ahamverifide.org/ahams-air-filtration-standards/), Clean Air Delivery Rates (CADRs) should be at least 2/3 of a room's area (assuming an 8 ft. ceiling height). Your room is 676.5 sq. ft. Therefore minimum CADRs should be **451 CFM**. You may need even [higher CADRs in certain circumstances](https://www.reddit.com/r/AirPurifiers/wiki/index/how_to_choose_an_air_purifier_for_particulates/#wiki_when_higher_than_normal_cadrs_may_be_needed). The best purifier Costco offers is the **Winix C909** ([$199.99](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi-%2526-plasmawave-technology.product.100842491.html)), which is online only. Its CADRs (for dust, pollen, and smoke) are in the 300s CFM which are too low. You would need two Winix C909 units for this room. A few drawbacks to the C909: Winix is more a mid-grade brand. We've had reports of units developing whining, whirring, or clicking noises after the 2 year mark. This is usually an issue with bad motor bearings. The C909 is loud on its highest setting ("Turbo") at 60 dBA according to the Decibel X Android app. It's also not the most energy efficient, using 95 W on Turbo. If you have pet birds, keep the PlasmaWave ionizer off. I would *avoid* the Winix XQ, in case you're curious. [A number of reviews at Winix](https://www.winixamerica.com/product/xq/) claim this model fails completely within a few years.

Shark is lower quality and uses misleading marketing. Take "NeverChange". It claims you don't need to change the filter for up to 5 years. If you look on the product page, the NeverChange applies to a much smaller square footage, specifically 300 sq. ft. This is also mentioned in the manual: >"Tested to GB/T18801-2015 P.CCM, based on 50% CADR declined, 300 sq. ft. cleaning area and 12 hours daily operation on MAX fan speed." A filter's time to saturation depends on pollution levels. The coverage is also overblown for the HP302 model. You're only getting 1 Air Change per Hour (ACH) at 1,400 sq. ft. The minimum ACH would be 4.8-5 ACH in normal pollution circumstances. The absolute largest room size in which I'd use a the Shark is 306 sq. ft. (assuming an 8 ft. high ceiling) according to the [AHAM 2/3 rule](https://ahamverifide.org/ahams-air-filtration-standards/). I would return the Shark and buy the [Winix C909](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi--plasmawave-technology.product.100842491.html) instead.

No, one [Winix C610](https://www.winixamerica.com/product/c610/) wouldn't be enough. The [Winix 5510](https://www.winixamerica.com/product/5510/) would be underpowered too. I would base my choice off of Clean Air Delivery Rates (CADRs), not Air Changes per Hour (ACH). See the AutoModerator comment about the [AHAM 2/3 rule](https://ahamverifide.org/ahams-air-filtration-standards/). For an open 500 sq. ft. space, *minimum* Clean Air Delivery Rates (CADRs) should be **334 CFM**. This assumes the ceiling height is 8 feet. The Winix C610 has CADRs of: * Dust: 252 CFM * Pollen: 262 CFM * Tobacco Smoke: 248 CFM If you want a conventional HEPA purifier, it's going to be hard to find one unit that isn't very expensive and large. A model that is slightly short on dust and smoke CADRs is the [Coway Airmega 400](https://cowaymega.com/products/airmega-400). (The [Coway Airmega ProX](https://cowaymega.com/products/airmega-prox) exceeds min. CADRs, but it's large and very expensive.) The [Alen BreatheSmart 75i product page](https://alen.com/products/alen-breathesmart-75i-air-purifier?variant=13172054491203) claims an averaged (?) CADR of 375 CFM with a big price tag of $799. This is probably using the "Pure" Allergen Collector filter. [Energy Star says the BreatheSmart 75i (version 2.0)](https://www.energystar.gov/productfinder/product/certified-room-air-cleaners/details/3417462) has CADRs of: * Dust: 351 CFM * Pollen: 431 CFM\* * Smoke: 370 CFM \*Likely with the ionizer turned on. Turning the ionizer off will probably decrease Pollen CADR. Alternatively, you can buy multiple smaller purifiers whose combined CADRs meet or exceed the minimum 334 CFM values. Just remember that CADRs for purifiers are for the highest airflow speed/setting only. Lower settings have lower CADRs.

Ah okay, there wasn't a budget in your post. You have the option of making your own Corsi-Rosenthal box with MERV 13 furnace filters ([ideally with PC fans](https://itsairborne.com/pc-fan-corsi-rosenthal-guide-a611dabf7e0c) for quieter and more energy efficient operation). MERV 13 is less efficient than HEPA standard filters, meaning it captures fewer particles of certain sizes on a single pass. But MERV 13 allows for more passes through filters faster which increases CADRs. Note: most C-R box configurations do *not* have a fine mesh pre-filter. Without these pre-filters, the MERV filters can clog faster with coarse particulates such as pet hair and visible dust. A less DIY option is the **AirFanta 3Pro**. It uses proprietary Efficient Particulate Air (EPA) E11 filters. EPA E11 is two filter classes below HEPA H13 in the EN 1822-1:2019 standard. Top composite CADR for the CARB Edition is 413 CFM. The 3Pro may be somewhat loud on the highest airflow speed. It has metal grating protecting the filters, but no fine mesh pre-filters so it could clog sooner due to coarse particulates. [Price is $159.99](https://air-fanta.com/products/airfanta-3pro). If you still want a conventional HEPA purifier, an option that meets or is close to minimum CADRs would be the **Winix C909** from [Costco.com ($199.99)](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi-%2526-plasmawave-technology.product.100842491.html). I own one. On its highest speed called "Turbo", sound levels were 60 dBA according to the Decibel X Android app, so it may be a bit loud. Again, if you want to keep PlasmaWave (bipolar ionizer) off, it will likely decrease Pollen CADR.

The [C909 CADRs are definitely on the Costco page](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi-%2526-plasmawave-technology.product.100842491.html). Click on the "Specifications" tab. * Dust: 336 CFM * Pollen: 384 CFM * Smoke: 323 CFM Disabling PlasmaWave will likely affect Pollen CADR negatively. And the CADRs listed here are for the highest airflow speed/setting only, called "Turbo". Lower settings will have lower CADRs.

Yes, I think so (although I've never owned a Coway). I have a [Winix C909](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491) from Costco. Based on feedback in this sub, Coway has better build quality, is more energy efficient, offers better warranties, and is quieter than other consumer-grade brands. Winix purifiers are more mid-quality. There's the possible issue of bad motor bearings cropping up after the 2 year mark. Winix tends to be louder and less energy efficient than Coway. But most Winix models offer smart features via an app and the filters tend to be cheaper for models. The latter is *not* the case for the [Winix 5510](https://www.winixamerica.com/product/5510/) and [Winix 5520](https://www.winixamerica.com/product/5520/) yet. Currently the genuine [Winix Filter Q – 1712-0123-00 set](https://www.winixamerica.com/product/filter-q-1712-0123-00/) tends to be full price ($79.99) from Winix and many retailers. If you'd like a recommendation for other models, please see **Rule 4** or the AutoModerator comment. Room dimensions (length x width x height) are very important.

Please read the AutoModerator comment. Air purifiers aren't good at reducing *visible* dust as it's larger and heavier than "invisible" pollutants like PM10 and PM2.5. The same goes for pet hair. Sans is terrible. Shark is mediocre. Avoid both. Coway is generally one of the highest quality consumer-grade brands. Winix is good, more mid-grade. Blueair has an always-on ionizer. Some people want to avoid this because of possible health effects associated with ionizers or changes in gaseous air chemistry. Per the AHAM 2/3 rule, a space 600-800 sq. ft. needs minimum Clean Air Delivery Rates (CADRs) of 400 CFM - 534 CFM. Unfortunately your budget doesn't support a single large or multiple conventional HEPA purifiers. (An example that meets CADRs would be the [Coway Airmega ProX](https://cowaymega.com/products/airmega-prox).) If you still want a conventional HEPA purifier, go with the [Winix C909 at Costco](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491). It's a bit of an energy hog (95 W) and somewhat loud on the highest setting called "Turbo" (60 dBA per the Decibel X Android app), but it's good value for money. The C909 has PlasmaWave, a bipolar ionizer. You may want to keep this off if you have pet birds. Another option may be the [AirFanta 3Pro](https://air-fanta.com/products/airfanta-3pro). It uses Efficient Particulate Air (EPA) E11 filters, which is two filter classes below HEPA H13. Top composite CADR is 413 for the CARB Edition. Price is $159.99. Keep in mind CADRs listed by purifiers apply to the highest airflow speed/setting only. Lower settings have lower CADRs which reduces cleaning effectiveness.

I have a Winix C909.

See the AutoModerator comment. Air purifiers aren't good at reducing *visible* dust as it's large and heavy compared to "invisible" pollutants like PM10, PM2.5, and PM0.1. Is your Dad's asthma triggered by dust *mites*? You can kill off dust mites by reducing relative humidity (RH) below 50% for prolonged periods (one study suggests 45% RH). You have a couple options. The [Winix C909 at Costco Canada is on sale for $229.99 CAD](https://www.costco.ca/winix-c909-4-stage-air-purifier-with-wifi-and-plasmawave-technology.product.4000257649.html). Top Smoke CADR is 323 CFM. Winix is a mid-grade brand. We've had some reports of whining, whirring, or clicking noises after the 2 year mark. This is usually caused by bad motor bearings. On the highest airflow setting called "Turbo", sound levels are 60 dBA according to the Decibel X Android app. The C909 also has PlasmaWave, a bipolar ionizer. You may wish to turn this *off* in case it aggravates your Dad's asthma. The Winix Filter A – 115115 set can be found at [Costco Canada](https://www.costco.ca/winix-replacement-filter-pack-for-winix-air-purifiers-2-pack.product.100694647.html) (identified as " Model 113151") and [The Home Depot Canada](https://www.homedepot.ca/product/winix-replacement-filter-a-for-p300/1001103938). An alternative is the [Coway Airmega 350, which is currently on sale for $370.30 CAD](https://cowaymega.ca/products/airmega-350). The Airmega 350 has higher Smoke and Pollen CADRs than the Winix. It uses an integrated pre-filter which isn't as easy to clean as a separate permanent pre-filter. This model does *not* have an ionizer. As of writing, the Airmega 350's replacement filters aren't on Coway's website yet. They should be in the near future. The [Airmega 350 "Fresh Starter" filter is for sale on Amazon Canada](https://www.amazon.ca/AIRMEGA-FILTER-FRESH-STARTER-PLUS/dp/B0F5V96F56/). ✳️ Keep in mind the CADRs listed for these purifiers applies to the highest airflow speed/setting only. Lower settings have lower CADRs which reduces cleaning effectiveness. ✳️

Costco sells filters for the models they carry. For the [Winix C909](https://www.costco.ca/winix-c909-4-stage-air-purifier-with-wifi-and-plasmawave-technology.product.4000257649.html), the [Filters A set (2-pack) is here](https://www.costco.ca/winix-replacement-filter-pack-for-winix-air-purifiers-2-pack.product.100694647.html). You can also find the set at [The Home Depot Canada](https://www.homedepot.ca/product/winix-replacement-filter-a-for-p300/1001103938). For the [Winix C545](https://www.costco.ca/winix-c545-air-purifier-with-true-hepa-filter-set.product.4000175806.html), the [Filter S set is here](https://www.costco.ca/winix-replacement-filter-s-for-winix-air-purifiers.product.4000225605.html). And the [Winix C610](https://www.costco.ca/winix-c610-4-stage-air-purifier-with-wifi-and-plasmawave-technology.product.4000286125.html)'s [Filters Z (2-pack) is here](https://www.costco.ca/winix-genuine-replacement-filter-z-2-pack.product.4000350899.html).

No worries - occasionally people wrongly believe their air purifier has an air conditioning function, so I just wanted to be clear. (I have a Winix C909 that makes me feel cold despite being dissimilar to the Coway Airmega Aim.) I would try to buy a purifier with a high top CADR given Dehli's pollution. The best value for CADRs appears to be the [Cuckoo Respure Air Purifier (CAC-R1510FW)](https://cuckooindia.in/collections/air-purifiers/products/cuckoo-r-air-purifier). Top CADR is 408 m^(3)/h. This CADR applies to the highest airflow speed/setting only. Lower settings have lower CADRs. Unfortunately I don't know much about Cuckoo as a brand, as it has a limited presence here in the USA and few experiences described in this subreddit.

Great, thanks. If it's a standard height, it's probably 8 ft. I assume these rooms are separated by walls? (Freestanding purifiers can't overcome walls and doors.) I saw elsewhere you're looking to reduce light cooking odors. It won't be possible with the Coway Airmega AP-1512HH Mighty pictured as it has very little capacity for removing gases, vapors, or odors. Ideally, there would be a vented range hood that exhausts to the outdoors. The next best solution is to exhaust via a window and a fan. Gases, vapors, and odors usually need pounds of a sorbent medium like activated carbon for effective and longer-term removal. Another issue: have your window AC units been cleaned recently? As for purifier particulate CADRs: * Minimum CADRs for bedroom: 205 CFM * Min. CADRs for kitchen: 187 CFM * Min. CADRs for living room: 136 CFM I don't know your sensitivity to allergen triggers. But I would recommend seeking out CADRs a good deal higher than the ones here - possibly 100 - 150 CFM more. I might recommend something like at least two **Winix C909** units at [Costco.com for $199.99](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi-%2526-plasmawave-technology.product.100842491.html) each, as they're very good value for money. A few notes: the C909 is loud on its highest setting called "Turbo" - the Decibel X Android app says it's 60 dBA. The Costco version gives you an extra HEPA filter. It's also not the most energy efficient model (95 W), but its replacement filters are very cheap at [The Home Depot](https://www.homedepot.com/p/Winix-True-HEPA-4-Filter-Activated-Carbon-Replacement-Filter-A-115115/202034412). Lastly, if you have pet birds, keep PlasmaWave (the ionizer) off.

I have a [Winix C909, which is currently on sale from Costco for $159.99](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491). I'm mentioning it because I've measured sound levels (with a smartphone app), the preferrable separate permanent pre-filter, and [cheap filter replacements from The Home Depot](https://www.homedepot.com/p/Winix-True-HEPA-4-Filter-Activated-Carbon-Replacement-Filter-A-115115/202034412). The C909's top airflow speed/setting called "Turbo" is 60 dBA according to the Decibel X Android app. The second highest speed/setting is around 48-49 dBA. If you want to save more money, see the [Winix C610 at Costco for $129.99](https://www.costco.com/p/-/winix-c610-4-stage-true-hepa-air-purifier-with-wi-fi-and-additional-filter/4000295784). It has an integrated pre-filter and lower top Clean Air Delivery Rates (CADRs) than the C909. I believe all Winix models with Wi-Fi capability can be controlled via Alexa. You may want to ask Winix for a definitive answer. Unfortunately brand name purifiers don't have non-proprietary filters. While there are usually third party filters, they may not perform as well as genuine filters.

Air purifiers aren't good at capturing pet hair as it's very large and heavy compared to PM2.5. See our [sticky post about dust](https://www.reddit.com/r/AirPurifiers/comments/1jxgjwf/sticky_purifiers_and_dust_reduction/) (which applies to pet hair as well). Per the [AHAM 2/3 rule](https://ahamverifide.org/ahams-air-filtration-standards/), your bedroom requires a minimum of 200 CFM CADRs. The living room requires a bare minimum of 334 CFM CADRs. Since you have pets and someone has an autoimmune condition, I would definitely go beyond minimum CADRs. The **Winix C909** ([$199.99](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi-%2526-plasmawave-technology.product.100842491.html)) from [Costco.com](http://Costco.com) would be very good fit for the bedroom. Keep PlasmaWave off if you have pet birds. However, it would come up a bit short in Smoke CADR (323 CFM) for the living room. Once you need 330 CFM CADRs and greater, it's hard to spend less than $200 on a conventional HEPA purifier or purifiers. You'd have to sacrifice single pass efficiency and/or build your own setup to stay under your budget. Alternatives include: **DIY Corsi-Rosenthal box with MERV 13 furnace filters**: [these can be made with PC fans](https://itsairborne.com/pc-fan-corsi-rosenthal-guide-a611dabf7e0c) which are quieter and more energy efficient than a box fan. MERV 13 is lower efficiency than HEPA H13/H14 on a single pass, but has less resistance and can therefore deliver high CADRs. Most configurations do not specify a fine mesh pre-filter, so the MERV filters could clog sooner with pet hair and dust. Top CADRs will depend on build, filter size, and the size/number of fan(s). **AirFanta 3Pro**: uses proprietary Efficient Particulate Air (EPA) E11 filters. EPA E11 is two filter classes below HEPA H13 and therefore less efficient on a single pass. However, it typically has a higher efficiency than MERV 13. Top composite CADR for the CARB Edition is 413 CFM. Highest speed may be fairly loud. Drawback: there are no fine mesh pre-filters, only metal guards. The filters could clog quickly with pet hair and dust. Price: [$159.99](https://air-fanta.com/products/airfanta-3pro).

The Coway Airmega 150 is less powerful (in terms of CADR) than the Cuckoo Respure. Generally you have to pay more money for quieter performance in air purifiers. That being said, 65 dB is quite loud for 250 CFM. My Winix C909 on the highest setting ("Turbo") measured 60 dBA according to the Decibel X Android app.

See the AutoModerator comment. Purifiers aren't good at reducing *visible* dust as it's large and heavy compared to "invisible" pollutants like PM10, PM2.5, and PM0.1. A Corsi-Rosenthal box with [MERV](https://www.epa.gov/indoor-air-quality-iaq/what-merv-rating) 13/14 furnace filters would capture more dust, but wouldn't significantly reduce it. See our other subreddit resources on dust: * [I need an air purifier for dust. What should I buy?](https://www.reddit.com/r/AirPurifiers/wiki/index/faqs/#wiki_i_need_an_air_purifier_for_dust.__what_should_i_buy.3F) * [Why is there visible dust despite running an air purifier?](https://www.reddit.com/r/AirPurifiers/wiki/index/faqs/#wiki_why_is_there_visible_dust_despite_running_an_air_purifier.3F) * [What else can I do to reduce dust?](https://www.reddit.com/r/AirPurifiers/wiki/index/faqs/#wiki_what_else_can_i_do_to_reduce_dust.3F) (⬅️ Try as many of these strategies as possible) Conventional HEPA purifiers work far better for most pet dander particles and pollen. Minimum Clean Air Delivery Rates (CADRs) for a 247 sq. ft. room would be 165 CFM. But since your brother has severe allergies, I would choose CADRs to 247 CFM or greater. For each room, I would recommend the [Winix C909 from Costco](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491) (currently on sale for $159.99). Winix is more a mid-grade brand. Top airflow setting is somewhat loud at 60 dBA according to the Decibel X Android app and it's a bit of an energy hog (95 W). But replacement filters are very cheap throughout the year at [The Home Depot](https://www.homedepot.com/p/Winix-True-HEPA-4-Filter-Activated-Carbon-Replacement-Filter-A-115115/202034412). Keep in mind CADRs apply to the highest airflow speed/setting only. Lower settings have lower CADRs which reduces cleaning effectiveness.

The Winix C909 has higher Clean Air Delivery Rates (CADRs), greater coverage at 4.8-5 Air Changes per Hour (ACH), and uses a separate permanent pre-filter compared to the C610. Definitely better than the C610.

Most combination units (e.g., purification + heating) perform one or more functions badly. Avoid Dyson. It's all marketing; they offer lousy particulates cleaning for the price. If you need to tackle particulates like dander *and* gases/vapors/odors, you need two types of air purifier. This is because most units have very little activated carbon or other sorbent media by weight. **On particulates purifiers:** Per the [AHAM 2/3 rule](https://ahamverifide.org/ahams-air-filtration-standards/) (in the AutoModerator comment and elsewhere), a 1,000 sq. ft. space with an 8 ft. ceiling needs minimum CADRs of 667 CFM. This is very high and very few consumer-grade units have sufficient CADRs. You may need to combine a Corsi-Rosenthal box design alongside a conventional HEPA purifier. Examples of C-R boxes are totally DIY units or the [AirFanta 3Pro](https://air-fanta.com/products/airfanta-3pro). Examples of the latter are the [Coway Airmega ProX](https://cowaymega.ca/products/airmega-prox) and the [Smart Air Blast MKII](https://smartairfilters.com/en/product/blast-commercial-hepa-air-purifier/). Edited to add: if you want to order directly from Coway, use **COWAYMEGA10** for an extra 10% off. See this guide for DIY Corsi-Rosenthal boxes with PC fans: [https://itsairborne.com/pc-fan-corsi-rosenthal-guide-a611dabf7e0c](https://itsairborne.com/pc-fan-corsi-rosenthal-guide-a611dabf7e0c) Two [Winix C909 units from Costco Canada](https://www.costco.ca/winix-c909-4-stage-air-purifier-with-wifi-and-plasmawave-technology.product.4000257649.html) would still fall a little short on minimum CADRs. The C909 features PlasmaWave, a bipolar ionizer. Keep this off if there are any pet birds as it could harm or kill them. (PlasmaWave defaults to being enabled after a power off/power on cycle.) **Gases/Odors/Vapors/VOCs:** Try to maximize all other means of source control first. These include optimized meat diets, stainless steel litter boxes, odor-reducing cat litters, enzymatic spray cleaners for cat urine, etc. From there, you may want to increase any kind of ventilation to dilute gases/odors. The last consideration would be a sorbent media purifier. You need pounds of sorbents for longer-term removal. For certain components of cat odors like ammonia (NH₃), you need chemically treated sorbents to increase removal efficiencies. The cheap option is the [Oransi TrueCarbon 150C](https://oransi.com/products/truecarbon-150c-air-purifier). It has 3.2 lbs. of potassium permanganate (KMnO₄) impregnated activated carbon. Just one of these could saturate quickly. Heavyweight sorbent media purifiers are very expensive and very loud. They tend to use plain/chemically untreated sorbents as standard, but you can usually specify KMnO₄ impregnated media or alternative blends. Example brands are Airpura and AllerAir. NB: KMnO₄ can oxidize certain gases. It's possible problematic byproducts could be created as a result. Usually this is an issue in a totally unknown and/or highly complex air chemistries, like chemical spills or fires in the built environment. KMnO₄ may also off gas as it loses efficacy or saturates.

Both will definitely help. On the highest airflow speed called "Turbo", the sound levels directly in front of one will be 60 dBA according to the Decibel X Android app. (I have a C909 and took the measurement.) Two running on Turbo would be 63 dBA. Some may find this quite loud. One Coway Airmega ProX or Smart Air Blast MKII would be quieter on the top airflow speed, but it doesn't come cheaply as I'm sure you've seen.

I would say the [Winix C909 from Costco](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491?langId=-1).\* Top Smoke CADR is 323 CFM. Winix units occasionally develop bad motor bearings after the two year mark which presents as a whining, whirring, or clicking noise. I've had a C909 since August 2024 with no problems yet. It's usually on the second highest airflow speed and when out of the room, Turbo. Coway is higher quality, but costs more per CADR than Winix. Alternatively, you could look into the [Levoit Vital 200S-P](https://levoit.com/products/vital-200s-p-smart-air-purifier) which is similar in CADR performance to the Winix 5500-2. As for the Corsi-Rosenthal box allusion, these are typically constructed with [MERV](https://www.epa.gov/indoor-air-quality-iaq/what-merv-rating) 13 or MERV 14 filters. And you do get higher CADRs for less money than conventional HEPA purifiers. If you want to go the C-R route, I would recommend using PC fans as these are much quieter and more energy efficient than a box fan. A guide: [https://itsairborne.com/pc-fan-corsi-rosenthal-guide-a611dabf7e0c](https://itsairborne.com/pc-fan-corsi-rosenthal-guide-a611dabf7e0c) \*Out of stock at the moment. Hopefully will be back soon.

Per the [AHAM 2/3 rule](https://ahamverifide.org/ahams-air-filtration-standards/), you need minimum Clean Air Delivery Rates (CADRs) of 167 CFM for a 250 sq. ft. room. Coway is one of the highest quality consumer-grade brands with good energy efficiency. But they tend to be more expensive. I would go with the [Winix C909 from Costco](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491). It has higher Clean Air Delivery Rates (CADRs) than the Winix 5510 and Winix 5520. Unfortunately it's out of stock at the moment. I'd hold out if possible.

An 800 sq. ft. room needs minimum CADRs of 534 CFM. If the room is 600 sq. ft., min. CADRs should be 400 CFM. The Coway Airmega ProX would absolutely be needed for the 800 sq. ft. space. Something like the [Medify Air MA-112](https://medifyair.com/products/ma-112?variant=31240021180483) is cheaper, but it's loud on the highest airflow speed (sound power level of 68 dBA). If you want just good or average quality, you could look into *two* [Winix C909 purifiers from Costco](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491).\* Top Smoke CADR is 323 CFM. It's somewhat loud on the highest airflow setting called "Turbo" (60 dBA according to the Decibel X Android app). Some Winix units develop bad motor bearings after the 2 year mark; this manifests as a whining, whirring, or clicking noise. The C909 has PlasmaWave, a bipolar ionizer. If birds will be in the house at any point, be sure to keep PlasmaWave *off* as it could harm them. (PlasmaWave is enabled by default after a power off/power on cycle.) \*Currently out of stock; should be back somewhat soon.

Per the AHAM 2/3 rule, a 950 sq. ft. space needs minimum CADRs of 634 CFM. If you have elevated particulate matter pollution, higher CADRs would be recommended. If you're prone to wildfire smoke, the Smoke Clean Air Delivery Rate (CADR) needs to *equal* a room's square footage (assuming an 8 ft. high ceiling) at the least. The purifiers you mentioned are underpowered for the total space. The Winix 5500-2 has been phased out in the USA market. The [Winix 5510](https://www.winixamerica.com/product/5510/) and [Winix 5520](https://www.winixamerica.com/product/5520/) are its successors. The [AirDoctor 4000](https://airdoctorpro.com/product/airdoctor-4000) has a higher Smoke CADR than the two Winix models. But AirDoctor filters can be really expensive. Your budget doesn't accommodate 100% conventional HEPA purifiers. You may able to do a combination of conventional HEPA and non-conventional air cleaners. I would consider the [Winix C909 sold at Costco](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491). Top Smoke CADR is 323 CFM. But it's a bit of an energy hog (95 W max) and somewhat loud on Turbo (60 dBA according to the Decibel X Android app). The C909 has an optional bipolar ionizer called PlasmaWave. Keep PlasmaWave *off* if there are ever birds in your apartment as it could harm or kill them. (NB: PlasmaWave defaults to being enabled after a power off/power on cycle.) You may want to consider *three* [AirFanta 3Pro](https://air-fanta.com/products/airfanta-3pro) purifiers. They use Efficient Particulate Air (EPA) E11 filters which is two filter classes below HEPA H13. Top composite CADR for one unit is 413 CFM. You could also fully DIY large Corsi-Rosenthal boxes with [MERV](https://www.epa.gov/indoor-air-quality-iaq/what-merv-rating) 13/14 filters and PC fans. CADRs will depend on airflow speed, # of PC fans, # of filters, and filter size. For C-R boxes, we usually recommend [3M Filtrete MPR 1900 MERV 13 filters](https://www.filtrete.com/3M/en_US/p/d/b00039899/). Costco sells the [3M Filtrete MPR 2500 MERV 14 filters in a 4-pack](https://www.costco.com/p/-/filtrete-air-filter-1-mpr-2500-merv-14-high-performance-premium-allergen-ultrafine-particles-bacteria-and-virus-filter-4-pack/4000181409) cheaply. A C-R box with PC fans guide: [https://itsairborne.com/pc-fan-corsi-rosenthal-guide-a611dabf7e0c](https://itsairborne.com/pc-fan-corsi-rosenthal-guide-a611dabf7e0c)

Purifiers are sized by each room or space generally. You'll get some reduction throughout the apartment with the doors open, but the percentage capture will be lower outside of the room where the purifier is located. See the AutoModerator comment. Purifiers aren't good at reducing *visible* dust as it's large and heavy compared to "invisible" pollutants like PM2.5. The best value in terms of initial price-per-Clean Air Delivery Rate (CADR) is the [Winix C909 from Costco](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491). Top Smoke CADR is 323 CFM. It's a bit of an energy hog at 95 W max. The highest airflow speed called "Turbo" is 60 dBA according to the Decibel X Android app. The C909 features PlasmaWave, an optional bipolar ionizer. If you have pet birds, ensure this is *off* as it could harm or kill them. Side note: PlasmaWave defaults to on after a power off/power on cycle. While the Winix C909 is CARB certified to produce very low ozone, PlasmaWave could be irritating to the baby. (NB: the [Coway Airmega Mighty AP-1512HH](https://cowaymega.com/products/mighty-ap-1512hh) also has the optional Vital Ionizer.) Infants and young children should not be exposed to overly loud air purifiers. According to a *Pediatrics* article, [US hospital nurseries have a recommended sound limit of 50 dBA](https://doi.org/10.1542/peds.2013-3617). Therefore if the baby's in the room, you may not be able to use the Turbo setting. The C909's next highest setting is about 48 dBA. If your budget limits you to one purifier, I would move it between the living room and bedroom... basically where the baby will be. As for best placement within a room, ensure you're not exhausting the air into curtains or window treatments. And don't place the purifier too close to the ceiling or underneath a table, nightstand, desk, etc.

Something like the [Coway Airmega 400](https://cowaymega.com/products/airmega-400) or [Coway Airmega 400S](https://cowaymega.com/products/airmega-400s?variant=33436459892871). But that's a really big increase in your budget. The [Winix C909 from Costco](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491) is a very-good-value-for-money HEPA purifier. It will probably be louder on the highest airflow speed than the Airmega 400/400S mentioned above (60 dBA on Turbo according to the Decibel X Android app). The C909 uses PlasmaWave, an optional bipolar ionizer. If you do or ever have pet birds, be sure to keep PlasmaWave off as it could harm or kill them (PlasmaWave defaults to on after a power off/power on cycle.)

Very good value for money is the [Winix C909 from Costco](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491). Top Smoke CADR is 323 CFM. It is a bit of an energy hog on the highest airflow speed (called "Turbo") at 95 W. If you have pet birds, keep PlasmaWave *off*. PlasmaWave is a bipolar ionizer. It creates a very small amount of ozone as a byproduct; birds are more sensitive to ozone and other air pollutants than humans.

Avoid Shark. They use misleading marketing ("NeverChange" filters), their AQI displays frequently have issues, and are a mediocre brand overall in terms of air cleaning performance. The [AHAM 2/3 rule](https://ahamverifide.org/ahams-air-filtration-standards/) assumes an 8 ft. high ceiling. In dividing your 3,200 cu. ft. by 8 ft., we get a coverage value of 400 sq. ft. Divide 400 sq. ft. by 1.5 for minimum CADRs of 267 CFM. CADRs listed by purifier brands apply to the highest airflow speed/setting only. Lower settings have lower CADRs which reduces cleaning effectiveness. You can achieve min. CADRs with one big unit (over your budget) or two smaller purifiers. E.g., you could buy two [Levoit Vital 200S-P](https://levoit.com/products/vital-200s-p-smart-air-purifier) purifiers, currently on sale for $149.99. Maximum Smoke CADR for each Vital 200S-P is 250 CFM. If you only want one unit, have a look at the [Winix C909 from Costco](https://www.costco.com/p/-/winix-c909-4-stage-air-purifier-with-wi-fi-plasmawave-technology/100842491). It's currently on sale for $159.99. Top Smoke CADR is 323 CFM. It's a bit of an energy hog (95 W) and may be fairly loud (60 dBA on "Turbo" according to the Decibel X Android app), but its initial price is very good value for money. And replacement filters are cheap at [The Home Depot](https://www.homedepot.com/p/Winix-True-HEPA-4-Filter-Activated-Carbon-Replacement-Filter-A-115115/202034412). If you have pet birds, keep the Winix's PlasmaWave *off*.

So unfortunately your budget is very low for: higher quality, the 1,200 sq. ft. basement, VOCs/odors, and for specifying a "quiet" air purifier (don't know what the dB/dBA threshold would be for you). The best value-for-money conventional HEPA air purifier is generally the **Winix C909** [sold on Costco.com](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi-%2526-plasmawave-technology.product.100842491.html). There are a few drawbacks. First, Winix is more of a mid-grade brand. There have been some reports of whirring, whining, or clicking noises after the 2 year mark. This is usually a problem with motor bearings, which some people elect to fix. Secondly, the C909 can be somewhat loud on the highest setting called "Turbo". I own a C909 and Turbo registered at 60 dBA on the Decibel X Android app. Lastly, keep PlasmaWave (the bipolar ion generator) off if you have pet birds. The C909 is on sale for 159.99 right now. Per the AHAM 2/3 rule mentioned in the AutoModerator comment, your basement needs at minimum **800 CFM CADRs**. You would need *three* Winix C909 units running at the highest speed to achieve adequate CADRs for the basement. A cheaper solution would be the **AirFanta 3Pro**. It uses proprietary Efficient Particulate Air (EPA) E11 filters, which is two filter classes below HEPA H13. EPA E11 has a lower single-pass efficiency than HEPA H13, meaning it filters less particulates on each pass. However, the AirFanta 3Pro has a higher CADR which means it can achieve more passes faster than a lower CADR HEPA filter. Top composite CADR is 413 CFM for the CARB Edition. [Price is $159.99](https://air-fanta.com/products/airfanta-3pro). There are some drawbacks for the 3Pro. First, it doesn't have a fine mesh pre-filter. The filters are protected by a metal grating. This means the EPA E11 filter media could clog faster with coarse particulates. Secondly, the highest setting may be quite loud. [HouseFresh](https://housefresh.com/airfanta-3pro-review/) measured the top setting at 56.3 dBA while [BreatheSafeAir](https://breathesafeair.com/airfanta-3pro-review/) claims 61.6 dBA at 2 meters distance. You would need *two* AirFanta 3Pros running at top speed in your basement to meet minimum CADRs of 800 CFM. As for VOCs and odors, I would recommend source control and ventilation first. Ventilation could be "fresh" (oxygenated) air drawn into a space or dirty air that's exhausted. Unfortunately you need many pounds of sorbent media (such as activated carbon) to deal with gaseous pollution. And heavyweight sorbent media purifiers are expensive.

I was going to build one with a box fan, but I figured this is probably just the new normal for summers going forward so I ordered one from Costco. Working well so far. [https://www.costco.ca/winix-c909-4-stage-air-purifier-with-wifi-and-plasmawave-technology.product.4000257649.html](https://www.costco.ca/winix-c909-4-stage-air-purifier-with-wifi-and-plasmawave-technology.product.4000257649.html) They also have one in store that does a little less area.

We just got the Winix c909 and the turbo setting is not that bad to sleep to

I have both and like this one better. The C909 is louder on low-high but about the same on turbo. You also can't turn the indicator lights off on the C909.

It does. If you don't mind it being slightly louder and somewhat bulky it's definitely a good air purifier. I like the filters in it better it has a washable pre filter. It also goes on sale occasionally

This one was $100 on sale and is supposedly rated for more Sq ft than the 535. I also have a C909 which is bigger and uses the same filters as yours but I personally prefer the 610.

Winix c909 goes on sale for 170 at Costco a couple times per year and comes with 2 filter sets. I’m not an expert, but I suspect this is probably the cheapest true-HEPA CFM per dollar in a smart device on the market. However, all the ratings are based on the highest fan setting, which is much louder and stronger than even the next lowest setting.

I bought the C909 that was on sale previously. It works well however developed the annoying whining sound. Apparently that's a frequent issue with those.

It does have a better air flow than the c545. But if you're allergic to the cat it might be worth switching them to one of the allergy cat foods. I've had no issues with the two c909s we have in our house. One I snagged from winix officially refurbished. But those can be hit or miss to catch and sell out pretty quick.

Yep as far as air purifiers the more the merrier. Especially if you don't want to run them loud. My house currently has 2xc909 2x545 and 1x5300 our air quality is pretty good so the filter lasts but it's great for pollen and other things.

I'm a fan of winix but largely because of after market filter prices. I have currently multiple c545 and a c909. If your budget /space is fine for the unit then there's no harm going larger if anything it will just let it clear the air faster and likely at a lower volume than a smaller unit would.

If you're in the USA it might be worth picking up two winix refurbished c545. They are pretty hard to beat at 69.99 tbh. I use them with the wifi off and no plasma wave currently have 2 of them and 2 of the c909 costco models in our house.

Winix is great for aftermarket filter options. For rooms we have smaller c545 that are pretty cheap refurbished direct from winix. And then our large valued area we have two c909s one I got from Costco online another I got for refurbished from winix. But stock is hard to come by for the refurbs direct from winix and sells out fast. When I buy filters off Amazon I normally look for multi packs 2,3 etc as normally you can get a better deal that way. Official filters get pricey really fast

C909s from Costco are pretty good cost to filter ratio if you need a lot. C545 for individual rooms is hard to beat for its price. For the Costco version it's 199 online retail the c909 is 329

Seems like a good air purifier but tbh. 700 seems like quite a lot. You could buy 3 and a half winix c909s from Costco online for the same price as one.

The winix c909 uses HEPA filters in it. Costco often also gives you an extra filter set in the box. Pretty amazing deal for 199 if you have a membership

Forgot to mention I don't recommend the new winix 5520 from Amazon over the c909 because it has a louder fan and lower cadr rating for basically the same price.