Winix - C535/C909

If you have a Costco membership the Winix C909 is the absolute best bang for the buck. It has a much great air capacity than the 5500-2 which means you can run it at a low (not noisy) setting and still handle a good amount of air (general guideline is that you want at least 5 air changes per hour to have a real benefit from an air purifier). The C909 is the same as the 9800, but it is a Costco exclusive. It is $199 and comes with two years worth of filters.

Oh, I mean I don't mean to discount anyone else's experience with it either. I'm just adding to the sample size. Figure this sub has at least a few hundred Winix owners who can chime in and add to the sampling. I've just been using Winix for a while and replacement filters are cheap. I still have 3 original 5500's from Winix still in use today - which is nice because it generally shares the same filter dimensions (except thickness) as the 5300-2 and 5500-2 - letting me slap on the bigger pellet sized carbon prefilters (sized for the 5500-2) on all 3 of these models (edit: and the Costco specific C535 - that also has similar filter dimensions).

There's a guy who did a youtube video on it - essentially the same filters except some of the prefilter and filter depth area is different. Meaning - the carbon pellet prefilter WILL NOT fit the 5300-2/C535. Basically you can try putting the carbon pellet cartridge/rigid filter in - but the mesh prefilter that clips on won't be able to "clear" it and lock into place flatly. If you don't mind a bit of bending or don't care to have a prefilter - it'll "fit". - But the filter can "fall out of place" since nothing is clipping it in. If its installed and the unit is never moved or knocked, the filters will stay in place - suction alone at speeds 3 and above can keep it fairly in place even when knocked around. The C535 and 5300-2 are basically the same. The 5500-2 is where the differences start - since the 5500-2 basically allows you to run any filters you want because it has the filter depth area to hold anything. Performance wise, they "feel" similar; acoustically - you wouldn't be able to tell filter to filter which is which unless one was defective or had something lodged inside the fan. For full disclosure - almost every single unit except for maybe 1 of my C535's are refurbished from Winix (often resold through woot/meh) which is why I have so many. (Usually I get them for $69/ea or less). So the act of "refurbishment" might have saved me from any defective noisy units. That or my batch - all of my 5500/5300's are over 6 years old. A quick check puts 3 of my C535's at 2018 vintage - and these are my newest units of the "5500" series. Summary: \- Remote control differences \- Different Filter Depth acceptance (5500-2 is larger) \- C535/5300-2 is the same \- Same acoustic performance \- Same airflow performance \- Carbon Filter differences

Hey OP. I've owned several different air filters over the years and they've all helped a lot to lower the dust level and subdue my allergies. Even the cheap ones do shit. One thing is you have to clean the filters! The pre- filter gets dirty. Fills up with dust. I do like the Winix filters from Costco. The one I've got came with extra filters, which is really nice, cause the filters are like printer ink.

This question has been asked a lot recently. I really like the Winix from Costco, about $100 and then turn off ionizers (produces small amounts of ozone). I barely get dust in my house since we run a few of them throughout the house.

Multiple Winix from Costco. Significant difference. Hardly any dust in our house. Affordable. Turn off ionizer on them!

That will go on sale from time to time for $99. The winix c909 costco carries is a better air purifier, which was down to $160 last week. it goes on sale every few months. the advantage of the costco air purifier is they come with a set or replacement filters so you essentially can run for 2 years. In my brief time in this thread, the square/rectangular purifiers are better then the circular ones. The winix c909 was a little to big for my bedroom, so I got the coway 160 which is plenty for my room. You need to figure how many square feet you need to clean, and then provide you with 4 air exchange an hour. The more the better, as you can run at lower speeds if noise is a concern.

I use a couple of Winix air purifiers from Costco. I have also used a Shark 3 in 1 clean sense. Both have HEPA filters and work well and are also pretty quiet, no problem with running them while I sleep.

yup had my winix since 2017. runs 24/7

Winix from Costco. It works well and at around $150 it comes with a bunch of replacement filters too

We have a Winix from Costco. We got 3 of them for around the house. We love them!

Winix from costco. I've stress tested it during a wildfire that got within a few miles of my home. I do not recommend Blue Air. Its more expensive and less effective.

We have a couple Winix purifiers from Costco and they're great. High CADR, compact, and they go on sale frequently. The HPA300 from Honeywell is also a great unit.

i have a winix from costco, but not this exact model its great. the filter is good for a year and the prefilter is good for 3 to 4 months. filter replacements can get pricey though so consider that before you purchase. although that would be 2 years down the line

filters are WAY overpriced considering you can get the machine with 2 filters for $120..

You don't need an expensive one, you just need one that seals well around the edges with a HEPA filter. You could even make one with a box fan, a filter and some tape. More expensive ones might have higher throughput or some other small advantages, but we've always just bought more rather than more expensive which allows for better targeting of specific areas like the bedrooms. The best value one I've found here is by [Winix at Costco](https://www.costco.com/air-purifiers.html?brand=winix&refine=%7C%7CBrand_attr-Winix). NOT the one they sell online. There's a white one that they frequently sell in the store. I've gotten it for as little as $130 on sale. It comes with 2 replacement filters as well I believe. I don't like it in the bedroom because the bearings on the fan aren't as good as some others so it will occasionally make a little clicking noise as the fan spins, but its perfect for other areas of the house. For the bedrooms we got this model by [Coway off of Amazon](https://www.amazon.com/dp/B01728NLRG). Nice and quiet, works well. Don't put humidifiers anywhere near the filters. It tends to trigger the sensors.

Just get something that uses HEPA filters. We have one in every room but the bathroom (humidity from the shower is not great for the filters). I've never had to clean baseboards since using them. Winix from Costco. I also have a Coway and Levoit (lots of people like those) as well as a few from Medify. They all do the same thing. I personally prefer to get one larger than needed for the size the room it's rated for so I can run it on low - which is quieter - and still get a good number of air exchanges per hour (the room size they typically advertise assumes you're running it on high which most people are not since the higher settings are loud). Bonus with HEPAs is that they help reduce illness transmission as they clean viruses from the air.

Winix from Costco tends to be one of the best bang for your buck and you can buy filter packs from Costco. Just turn off the ionize setting on them since ionizers create ozone.

As an alternative to the 5500-2, what about the C535? I picked mine up at Walmart because I wanted one last minute. It doesn't come with a remote, but it works perfectly with the 5500-2 remote, which probably won't help you unless you have an IR blaster.

Winix c535 from my local Walmart super center was around $170 out the door and it comes with 2 hepa air filters + 9 carbon filters.

They claim the two filters + carbon filters are good for 2 years total

That's a good one. Just don't rely on auto mode and you may want to buy some blackout stickers to reduce the amount of light coming from those super bright lights.

Credentials : I currently have a Golden and a St. Bernard, before them I had three Great Pyrnees,,,,at the same time. I've also owned 19 vaccuums 😂 I have two Shark robot vaccuums that run on a staggered schedule, constantly. Essentially, they're always "sweeping." I use a silicone broom ,too, and that works way better than I ever expected it to. I also mop with a bissel crosswave every day and swear by it. That takes care of our entire downstairs, which is all LVP flooring.  As for our regular vaccuum, we have a Kenmore Intuition, and I love it for all the carpeted areas. It comes apart just like a Shark- I can do the couch, the stairs, all the nooks and ceannies, etc- except the suction is way better than a Shark (I said what I said.) I don't deal with hair coiling around the brush head all that often so that hasn't been an issue for us.  We also use a silicone broom on all the furniture, in conjunction with a mattress vaccuum, and it works great. We have a Winix air purifier in every single room, I love them. The filters get vaccuumed once a week and we replace them every 6ish months. People always remark that our house doesn't smell like dog, which a huge achievement as a Saint owner lol.  As for the dogs themselves, they get brushed outside every three days, like clockwork. They also get deshedded and groomed regularly at the groomer. Constant brushing and regular grooming really helps with the allergy thing. The bed: duvet covers that get switched out once a week, sheets washed once a week as well. Being a dog owner is just a battlefield of dog hair, the best defense is having a good offense. Between the vaccums, the air purifiers and the grooming, we're doing okay. We may not be winning the war, but by God it feels like we've won some key battles.  Edit for spelling*

I'm on mobile browser so it's hard to link so I'll just tell ya! We have the C535 for all the common areas, and the C610 in all our bedrooms. Then for the bathrooms and pantry we use the LEVOIT Mini Cores (I like these for small areas, but I have to change the filters more frequently.) 

Fwiw after going down a similar rabbit hole to OPs I ended up buying the C535 from the Winix website. I think you can get the filters for that one from Costco but my memory kinda sucks.

Do have the Coway 250 as an option? I got one for $250 open box or refurbished on Amazon. It’s amazing. The sound it makes is very pleasant and it’s easy to clean, and aesthetic. The Coway or 240 is also a good choice and comes in white. The Winix 5500-2 or C535/C545 is also a solid choice and a bit more affordable. I believe Costco has good deals on the C545. Lastly, you could check local marketplaces. I got some Winix, and Blue Air purifiers (the 203 slim, 403, and 503) for a great price.

We bought a Winix. Like it so much that we bought another one. It comes with a set of replacement filters. You can also buy additional ones from Amazon.

One is a C535, the other is a C545.

Then that's good. I have the Winix Air Purifier, C535 with remote. $35 - $50 for a new generic filter. Winix filters are expensive.

Really! I bet $70 for 1. I buy the generic brand from Amazon for half the price and they work the same . My Winix is unbelievable. If you fart or even spray any chemicals, cooking. It turns red capturing all the odors from the chemicals. The orange, 10 minutes later it turns blue again. Even though the kitchen is far from the living room . I use my Dyson vac to clean the filter. Winix is a good product. I wouldn't buy yours because it's too small. $130 vs $200 = it's only $70 difference and I got the top of the line .

Winix is good but they keep changing the models in Costco and also the cost of the original filter is as expensive as the new purifier itself. However, you can get 3rd party filters from Amazon which can help lower that cost. The Winix 535 vs 545 the hepa filter size changes.

I have the Winix C535 (two of them) and they are great. Quiet, effective, easy to get filters for.

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.

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.

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.

I have a Winix c909 I got from Costco and I leave it on high in my bedroom for the perfect background fan noise. We used to have a box fan in the hallway and I got used to that noise and got rid of that fan for kid safety. This is the closest thing I’ve found. I think it would be the right size for your room, they have a similar one on the Winix website if you don’t have a Costco.

I have the feature turned off on all 3 of them, but I did leave it on for a day or so in two of the rooms when I got them to see if it made any differences or made us feel bad. It was in an office and a bedroom our pets and kid weren’t in, so kind of a safe test, I guess. I didn’t notice anything different. I guess some people get headaches or feel off. I did read that it can make the air drier and that’s definitely not something I want, so I’ve just turned it off on all of them. I recently found out I have a bunch of allergies- including my dog, so I got these Winix units to try and help combat the allergies. Within about 45 minutes of running one in my living room, part of my nose that has been clogged for as long as I can remember opened up. I’m breathing better than I have in years. We’re moving to a larger house soon, and I will absolutely pick up a couple more.

Thanks btw! I got the c909 and love it so far.

If you have an enclosed printer I really like the bentobox. You can build it yourself or buy online. I use mine on top of a winix c909 im the same room. https://www.printables.com/model/272525-bentobox-v20-carbon-filter-for-bambu-lab-x1c-enclo

Costco.com. Winix C909. Comes with 2 years of filters. Was in the same position as you last month. So far it’s great. We move it to the room we are spending the most time in (typically living room in the day, bedroom at night). Its auto mode is simple and it’s basically plug it in and walk away.

The Winix deal on Costco is unbeatable. Fits that budget and you get 2 years of filters.

Costco.com online only deal: Winix C909 for $199 https://preview.redd.it/v7hz6apnldpf1.jpeg?width=1290&format=pjpg&auto=webp&s=ea72fc051a16bc02fa4625962781cf0d016802db Comes with 2 years worth of air filters (stored inside the machine when it arrives to you- I had to figure that out lol). I was researching so many brands and even bought a couple on Amazon only to return them. The C909 is what I was looking for and works great.

I have a Winix C909 in the living room that I bought at Costco. I use the homebridge plugin to monitor when the TV is on, and then I have it automatically change from Auto mode to Sleep mode (quiet, but still on). When the TV is off, it goes back to Auto. Of course, if I had one that had a physical switch that could be left on auto/on, I could just have used a smart outlet instead.

If you are going Coway, rough estimate would be, you would need 2-400 for main room and 1-300 for each of the other rooms or could possibly get away with the Mighty for the kids rooms. Most of the carbon in Coway filters are not going to be a good amount if you are looking to maximize carbon filtration as many other air purifiers unless you get one that is 15-20+ pounds of carbon which will probably be $700-1200/each. If you are ok with the need for pre filter and hepa filter and want to go on a budget and stick to one filter for all, i would suggest Winix C909 at Costco or wherever there is a deal. I know Costco offers a few more filters as a bonus. Just my thouguts.

I have the Winix C909 and Coway Pro X. Yes they are completely in terms of size and need, but they both feel like nice quality to me. I use each in the appropriate size room and it feels the same to me 🤷🏻‍♂️. Only bought both when they were on sale though. I personally think Coway is only worth it on a good sale

Winix C909 from Costco if you have a large space.

You can get the Winix C909 at costco website for $160, with 2yrs worth of filter supplies included(sale end on 5/11, online only, discount limit 5 per customer, no membership required), and home depot sell 1yr worth of filter supply for the c909 at $27.99, it’s has one of the largest coverage area among winix air purifier(just behind the xq tower, which i dont recommend), the performance to price ratio is unmatch.

We had a Winix C909 for a year and happy with it. Quiet, effective and filter life seems to be long.

Yes, it will still accumulate. Dust can be made of various substances: dead skin, hair, animal dander, insect parts, outdoor (e.g., vehicle) pollution, carpet/rug fibers, bacteria, other textile fibers, pollen, soil particles, mold/mold fragments, microplastics, and dust mites + their droppings to name a few. You might be able to noticeably reduce visible dust if you ran a wildly oversized air purifier in a small space. But for example, my Winix C909 with a Dust CADR of 336 CFM in a \~175 sq. ft. room with an 8 ft. ceiling does not eliminate dust on the windowsills. Then again, I don't run it at the very top CADR most of the time either.

Because of the higher ceilings, your room's volume is 1,400 cubic feet. Divide 1,400 by 8 ft. to get **175 sq. ft.**, which is the figure you should be using. Air purifier coverage ratings are given in square feet, but they assume an 8 ft. high ceiling. I'm less keen on the HoMedics model because of the cylindrical design. Some cylindrical purifiers have underpowered motors which must spin at higher speeds to deliver adequate air flow. This causes them to burn out sooner potentially. Additionally, most cylindrical purifier filters have an integrated pre-filter. A separate permanent pre-filter is preferred for ease of cleaning off coarse dust without damage to the HEPA or other mechanical filtration underneath. Lastly, HoMedic's build quality and reliability may not be the greatest according to Consumer Reports feedback. Considering the AQI is very bad, I would consider the **Winix C909** which is sold at [Costco.com only](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi--plasmawave-technology.product.100842491.html). It has higher CADRs including Smoke CADR which means it can clean a room faster and more effectively. Winix is more mid-tier in quality and their purifiers are known for being loud on the highest setting ("Turbo"). * AHAM Verifide: 4.8 Air Changes per Hour at 500 sq. ft. * CADR Dust: 336 CFM * CADR Pollen: 384 CFM * CADR Smoke: 323 CFM * Power Consumption: 95W * Price: $199.99 There's a potential problem with electrostatically-charged MERV filters and smoke: in short, smoke particles may significantly impact CADRs. This is from an article by the Healthy Buildings program at Harvard called ["Protecting your Health from Wildfire Smoke – Spotlight on Filters"](https://healthybuildings.hsph.harvard.edu/protecting-your-health-from-wildfire-smoke-spotlight-on-filters/). Skip down to the **Impact of Wildfires on Filter Performance** heading. I've quoted it below: >Wildfires bring an additional layer of complexity to this performance decline issue. It is postulated that deposited smoke particles, which carry a charge \[23\], on these electrostatically-charged filters can either mask or counter the intended filter charge, thus reducing the intended electrostatic removal mechanism \[9\], \[21\]. A recent controlled chamber study demonstrated that the Clean Air Delivery Rate (CADR) of a Do-It-Yourself (DIY) air cleaner using 1 inch electrostatic MERV-13 filters is reduced significantly when the filter is loaded with smoke \[9\]. The researchers observed that the CADR of the DIY air cleaners equipped with electrostatic air filters was reduced by 95%, while airflow through the filter was maintained (only 7% increase in pressure drop), pointing to a loss in the electrostatic attraction mechanism as the likely cause of filter performance decline since airflow appeared to be maintained. This occurrence has been observed in other studies with cigarette smoke and intentionally discharging the filter with isopropyl alcohol \[9\]. Other studies that investigated longer term and more realistic test conditions note similar findings, with one study observing a substantial reduction in particle removal efficiency over a 19-week period of operation in an air handling unit that supplies outside air \[19\]. The exact mechanisms and magnitude of the decrease is difficult to predict in practice, due to numerous factors, such as the amount and composition of particle loading on the filter \[21\]. Nevertheless, reductions in filtration effectiveness can be up to a factor of two or more \[21\].

I would definitely address the airtightness issues with the windows if feasible—your energy costs and air quality control will improve greatly. Avoid both Bissell and Shark. What does your HVAC look like? If possible, you could upgrade to a "whole house" cabinet air cleaner. These are sold by HVAC equipment brands (Carrier, Lennox, Trane, American Standard, etc.) and by another company called AprilAire. Generally cabinet air cleaners have 4" to 5" thick filters, which offer more surface area, better filtration, and lower pressure drops than many 1" thick filters. While a higher MERV can capture more particulates, many residential HVAC systems cannot overcome the pressure drops of a MERV 16 filter. If necessary, you can consult a licensed HVAC contractor to do the load calculations and make a recommendation. If the budget's an issue, consider using 3M's 1" Filtrete Filters, specifically the Filtrete 1900 (MERV 13). In general, you will need at least one air purifier per room or area. With the high 12' ceilings, you need to calculate for room volume (W x L x H) instead of room area. Where air purifier coverage is given, it's in square feet. This measurement assumes an 8 ft. high ceiling. So if you want a purifier's volume coverage, just multiply the square footage rating by 8 feet. You can add multiple air purifiers to a space in order to increase Clean Air Delivery Rates (CADRs). Unfortunately most air purifiers aren't great for pet hair. Hair—relative to other much smaller particulates such as PM2.5—are large and heavy. Unless the hair is cast off very close to the purifier, it won't be caught in the pre-filter. Corsi-Rosenthal boxes using MERV 13 filters can have much higher air flow and capture more pet hair than most HEPA air purifiers. Vacuuming will be the best means of combatting pet hair. Generally Coway air purifiers are often recommended as they're higher quality and perform well. The exact model will depend on each room's volume. Winix is more mid-quality, but can be more affordable if you're on a budget. I own a Winix C909 which is sold at Costco and is a fantastic value given the CADRs. However, it is quite loud on the highest setting (Turbo). It's for removing particulates only and not gases. **Winix C909** * Room Size: 500 ft.^(2) in area or 4,000 cubic feet in volume * Tobacco Smoke CADR: 323 CFM * Dust CADR: 336 CFM * PM2.5 CADR: 330 CFM * Pollen CADR: 384 CFM * Power: 95 W * Price: $199.99 at [Costco.com only](https://www.costco.com/winix-c909-4-stage-air-purifier-with-wi-fi-%2526-plasmawave-technology.product.100842491.html) Other recommendations could be Smart Air, specifically the **Smart Air Blast MKII Air Purifier**. It's very quiet (43 dBA), has a metal body with locking wheels, and has a top Composite CADR of 559 CFM, but it's very expensive at $929.00. Power consumption is 118 watts. **Medify Air** makes some very high performance CADR purifiers, but quite a few—such as the [MA-112](https://medifyair.com/collections/all-products/products/ma-112)—are very loud (at 70 dBA). Except for their MA-112, most other Medify Air models have integrated pre-filters which are overlaid on the HEPA media. This is a problem as the pre-filter needs regular cleaning and it's very easy to damage the HEPA media underneath (especially if you're using a vacuum).

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.

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.

Winix is a good brand. I have the C909. You have to spend 5x more if you want true odor control. The little carbon filter isn't doing a whole lot. /r/AirPurifiers is a good source. Mine came with enough carbon filters to change them monthly. Set a remind to do it. If you clean week and there is a pre-filter vacuum that out every week.

I have a Winix C909 from Costco. It sucks up a lot of dust. I have two smaller units in each of the kid's bedrooms that also suck up a lot of dust and run very quiet. With that I doubt I'm even at like half of what I'd need for my modest 1900sqft house. Like the comment says they make their money on replacement filters. You can buy generic if true HEPA isn't import. My pre-filters before you even get the HEPA will fill with dust. Ikea makes more visually appealing filters that IIRC score well on filtering.

Air purifiers in the 250-400 CADR range are mass produced volume products sold at reasonably low margins. The filters are similarly more affordable and can be found everywhere. Larger air purifiers don't really have any advantages. They're generally more expensive to purchase, power and maintain for the amount of air volume they handle. For 950 sq ft I'd buy 3 Blueair 211i or 3 Winix C909 (Costco model) purifiers. Remember that the AHAM rated square footage on these units is based on (1) running them constantly on the loudest turbo mode and (2) having a lowish 8 foot ceiling height. The Winix C909's are notably less efficient, but they have separately replaceable carbon filters and easier to clean prefilters (washable screens vs fabric). Also, if you're concerned about noise you could buy 4-5 of either of these filters and run them on high (instead of turbo) to get similar coverage. The typical recommendation is to hit 5x air changes per hour - essentially to clean the indoor air at a rate faster than it's typically being exchanged with outdoor air. In my experience hitting 6-10x air changes per hour is actually a significant improvement over 5x though.

Get the C909 if you’re at Costco. Online only. Way better

Ditch the circular C610. It’s not great. Winix uses ionizers, which you don’t want, so if you go with a Winix you want to make sure you can switch it off. The downside to Winix and Coway is that they are loud on the higher settings, so you want to get a more powerful unit than you need for your spaces so that you can run them on a lower speed. The c909 would work for all three of your spaces though. Assuming 8ft ceilings, Airmega 160 is going to be too small for your living room and barely good for your bedroom. 240 would be fine for all three rooms. Personally, I would go with Coway over Winix just because then you don’t have to worry about turning off the ionizer, but they are both good brands though.

I bought a few during COVID. A couple are cheap Costco ones (Winix), but one is a fairly expensive Coway Airmega 400. Can't say I noticed any difference in my health or in the amount of surface dust landing on furniture. I think to see any real reduction in dust settling on furniture, you would probably need to run them on high to get a lot of air movement, but the noise of them running on high is annoying IMO.

I’ve been really impressed by my Winix. I have a huge one that really seems to do the job. I change the filter once the year but vacuum it all out more often than that to keep it running really well.

I’ve been using my Winix with Plasmawave since 2019 without issue, and that includes moving about once per year. These units have held up to that. I can tell you they really work. I have a mold allergy, and mold is literally everywhere in outdoor or indoor air with spores just waiting to land in a suitable environment for growth, but I have no symptoms at home with my two small Winix. I also have pets. These reduce any odors from that, and they are at what one might consider end of life for a typical air filter system. 5 years is typical. 10 is incredible. I am not washing the pre-filter nearly as often as I should and am slow to replace the carbon and HEPA filters sometimes, so 5+ is just astounding in my case.

The PlasmaWave I looked at used an ionizer which is a huge no for me.

PlasmaWave is just a glorified ionizer. I personally cannot stand the scent of ionizers, it gives me headaches.

You want a HEPA filter and actual activated carbon granules-sometimes the activated carbon is just a paper thin layer-not doing much. For cost, consider replacement filter costs not just up front ones. I also like ones that have a sensor so you can leave it on “auto” and it will kick on when you cook or air gets worse without you having to keep track of it. Also don’t splurge on plasma ion or ozone or whatever else-mixed studies show it can react with chemicals to form more dangerous ones at worst and generally not much better at best. Right now you may want to sacrifice optimality for actually having something going to clean your air since it’s a time of high uncertainty. What’s in stock at home depot may be superior to the “best” air purifier that arrives in 2 weeks. Those caveats-no one can give better advice based on “feel” than what’s tests show-and wirecutter actually tested performance https://www.nytimes.com/wirecutter/reviews/best-air-purifier/ . If you prefer anecdotes, here are some of my experiences: Winnix has been in stock at home depot. I evacuated with my air purifier and I needed something to leave during cleaning to try and detox my pasadena apartment. It was in stock and had hepa+carbon-it seems to be working. Oransi is the one I evacuated with, love the looks, it really seems to work well, lots of aftermarket filters available-downside is that sleep mode sets fan speed to auto, I want it to just turn lights off and leave the fan mode. But It has lasted at least 6+ years. Levoit is what was at the apartment I evacuated to. It seems a little less powerful per dollar spent than my oransi, but it’s night mode turns off the lights while still letting you set the fan speed. My roommate left a Coway going in his room and that thing worked very well to prevent any smoke smell from settling, and it’s highly recommended by wirecutter. If I had to buy right now and I could get one in a reasonable timeline, it’s how I would go.

Any filter with a charcoal filter layer will help some (Winix is one brand commonly available at Costco…I also have a more elaborate Rowenta)…my Winix came with multiple charcoal layer replacements. Dealing with total incontinence here, and not to criticize your MILs efforts, but you might want to look into the actual sources of the odors. Chairs, clothes that sit around waiting for wash, previously soaked furniture or carpet? If bedding or fabric furniture smells and you can replace it, do so. I use a combo of Depends on my father, and all his sleeping or seating surfaces have a first layer of puppy pee pads (Costco has large ones that work well and are cheap), and then a fabric layer on top (whether sheets or a chair cover or towel, tucked into the sides of the chair). Once he’s wet, after I changes his pants all clothes and chair covers and bedding goes in the wash (3-5 loads a day).  For the mattress you can find on Amazon washable mattress covers (the whole bed ones don’t work that well but that’s my base layer and then a thicker more absorbent one that I fit across the middle section of his bed, and on top of that layered dog pee pads).  So again, not sure if any of this advice helps but this method works for me.

I have 2 Winix HEPAs that have been running 24/7 for 6+ years. I clean the screen every week or so, replace the carbon every month, and the HEPA every ~8 months.