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smyc305 17.8K Views
Sep 1, 2026 1:33 PM

Costco Members: Winix C909 4-Stage Air Purifier

$160

$200

20% off
+ $5 S&Hat Costco Wholesale
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Deal Details
Costco Wholesale has for its Members: Winix C909 4-Stage Air Purifier w/ WiFi & PlasmaWave Technology (1022-0228-00) on sale for $159.99. Shipping is $4.99.

Thanks to Community Member smyc305 for sharing this deal.

Features:
  • AHAM Verified up to 500 sq. ft. Room Coverage
  • Energy Star & UL Certified
  • Ultra-Quiet on Slowest Speed (25 db)
  • Wi-Fi Enabled for Instant Monitoring and Control
  • 2-Year Filter Supply: Includes 2 True HEPA replacement filters and 8 Activated Carbon Filters

Editor's Notes

Written by powerfuldoppler | Staff
  • This price matches our previous Frontpage Deal
  • $40 manufacturer's savings is valid 9/1/26 through 9/30/26. While supplies last.
  • Limit 5 per member.
  • This product is rated 4.6 out of 5 stars based on 950 customer reviews.
  • If you don't have a Costco Warehouse Membership, you can sign-up here

Original Post

Written by smyc305
Community Notes
About the Poster
Deal Details
Community Notes
About the Poster
Costco Wholesale has for its Members: Winix C909 4-Stage Air Purifier w/ WiFi & PlasmaWave Technology (1022-0228-00) on sale for $159.99. Shipping is $4.99.

Thanks to Community Member smyc305 for sharing this deal.

Features:
  • AHAM Verified up to 500 sq. ft. Room Coverage
  • Energy Star & UL Certified
  • Ultra-Quiet on Slowest Speed (25 db)
  • Wi-Fi Enabled for Instant Monitoring and Control
  • 2-Year Filter Supply: Includes 2 True HEPA replacement filters and 8 Activated Carbon Filters

Editor's Notes

Written by powerfuldoppler | Staff
  • This price matches our previous Frontpage Deal
  • $40 manufacturer's savings is valid 9/1/26 through 9/30/26. While supplies last.
  • Limit 5 per member.
  • This product is rated 4.6 out of 5 stars based on 950 customer reviews.
  • If you don't have a Costco Warehouse Membership, you can sign-up here

Original Post

Written by smyc305

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Community Reviews

The Winix C909 is a high airflow air purifier that works well for dust, pollen, and allergy relief, with reports of fewer allergies, less rash irritation, and pre filters that quickly collect visible debris. It uses the standard A filter with a carbon sheet, and the Costco bundle includes an extra filter plus Costco backing. The PlasmaWave ionizer defaults on, so it has to be turned off manually if desired, and WiFi control needs a 2.4 gigahertz network with no spaces in the network name. A bearing issue has also been raised on other Winix models, so long term reliability may be worth watching.

Common Questions (5)

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37 Comments

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Sep 2, 2026 6:19 PM
809 Comments
Joined Jan 2010
mystiqueskillzSep 2, 2026 6:19 PM
809 Comments
Thanks in for one!
Sep 2, 2026 6:46 PM
1.6K Comments
Joined Nov 2008
EchoTonySep 2, 2026 6:46 PM
1.6K Comments
I needed a new air purifier for over a month. I was waiting for Costco to drop the price... and then Winix had the c909 refurbished back in stock as of last week. I bought that one for $120. This is more expensive, but this one comes with an extra filter and has Costco backing. I wish I had waited.
Sep 2, 2026 7:03 PM
1.6K Comments
Joined Nov 2008
EchoTonySep 2, 2026 7:03 PM
1.6K Comments
Quote from Mr. Sparkles View quoted comment :
Plasmawave: aka ionizer
There is good reason to be concerned about ionizers and ground-level ozone. Ozone can impact those with pulmonary issues as it can reduce lung function by 10% or more. Winix's PlasmaWave tech appears to produce very little ozone and thus does not appear to be a significant issue if you accidentally leave PlasmaWave on.
Obviously, if you have a serious health condition, you should discuss the use of any ozone-producing technology with your doctors.
Sep 2, 2026 7:08 PM
1.4K Comments
Joined Jan 2014
Kemiho33Sep 2, 2026 7:08 PM
1.4K Comments
Quote from wahhutch9 View quoted comment :
Is there always a shipping charge at Costco? Seeing $4.99
No. Not always. But, this item is probably heavier than a lot of things they ship.
Sep 2, 2026 7:37 PM
567 Comments
Joined Mar 2008
BudarowSep 2, 2026 7:37 PM
567 Comments
Quote from pkny View quoted comment :
Is this a upgrade to the c454 and c610?
I've got several c610s and I still see lots of particulate floating in the air at night with lights off and under a bright flashlight so I'm giving this model a try.

Fyi... I read if you have allergies and air purifiers are "medically necessary" for your health, consult with your doctor and ask for a letter of medical necessity (LMN) which apparently allows for the purchase of necessary medical devices to be paid for using HSA funds. This is not medical, financial, or taxation advice so consult with your doctor, financial or tax advisor for guidance:-)!
Last edited by Budarow September 2, 2026 at 12:49 PM.
Sep 2, 2026 8:40 PM
2.5K Comments
Joined Feb 2005
DarnCrazySep 2, 2026 8:40 PM
2.5K Comments
Quote from pkny View quoted comment :
Is this a upgrade to the c454 and c610?
If you have the space, yes it is. It moves a lot more air than the other two and uses the standard "A" filter with the carbon sheet, not the fancier carbon pellets. That said, I have two of these C909 and they work well where I am to keep the dust and pollen more at bay.

Just note the C909 are only controlled via the buttons on the unit or using wifi and the Winix app which is a bit annoying. You must use a 2.4ghz wifi network without any spaces in the SSID name otherwise it'll fail to find the network.
Sep 2, 2026 8:41 PM
1.4K Comments
Joined Feb 2023
LivelySink338Sep 2, 2026 8:41 PM
1.4K Comments
Can the air filters be cleaned or does it have to be replaced? How long does each filter last?

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Sep 2, 2026 9:03 PM
13 Comments
Joined Nov 2022
MellowApparel120Sep 2, 2026 9:03 PM
13 Comments
This or the shark breathe clear max ?
Sep 2, 2026 9:50 PM
19 Comments
Joined Dec 2013
RazzleDazzle4Sep 2, 2026 9:50 PM
19 Comments
Is this an upgrade over the 5530?
Sep 3, 2026 12:34 AM
1.3K Comments
Joined May 2021
ImagineNoReligionSep 3, 2026 12:34 AM
1.3K Comments
Quote from radars View quoted comment :
Do you feel any difference in air quality after it is in your room such as less allergy symptoms?
Air quality is like hypertension. By the time you notice a difference, you're toast. Remember that the CDC recommends only respirators and HEPA filters for wildfire smoke, which is projected to kill tens of thousands of Americans every year in the next three decades.
1
Sep 3, 2026 12:34 AM
1.3K Comments
Joined May 2021
ImagineNoReligionSep 3, 2026 12:34 AM
1.3K Comments
Quote from dealferret View quoted comment :
The default is is for the ionizer (Plasmawave) to be on, so you have to remember to turn it off each time you ever turn your purifier on and off.

That said, the ozone generated by the Plasmawave is supposed to be really low so if I forgot to turn it off I don't see why there would be a concern.....
If you're using the machine to clean your air, why would you muck it up, even if just a little bit?
1
Sep 3, 2026 2:48 AM
303 Comments
Joined Aug 2009
dealferretSep 3, 2026 2:48 AM
303 Comments
Quote from ImagineNoReligion View quoted comment :
If you're using the machine to clean your air, why would you muck it up, even if just a little bit?
Agreed, I always try to turn it off. I am just saying if I forgot to turn it off, I am not going to stay up all night thinking about it. If anyone here is concerned, they can choose to not buy Winix.
1
Sep 3, 2026 4:42 AM
1.1K Comments
Joined May 2004
roykirk1Sep 3, 2026 4:42 AM
1.1K Comments
Where should you place these things? Can I stick in the corner of the room? Or does it work a lot better if I put it in the center of the room? Thanks
Sep 3, 2026 5:35 AM
5.2K Comments
Joined Feb 2005
zoglogSep 3, 2026 5:35 AM
5.2K Comments
Noctua should make air purifiers

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Sep 3, 2026 5:43 AM
414 Comments
Joined Aug 2023
I_like_feetSep 3, 2026 5:43 AM
414 Comments
Quote from rubiks View quoted comment :
Are these made in Korea or Thailand? I have 535 and 545. 535 is made in Korea while 535 is Thailand. 535 is significantly better.
Excuse you! I'll have you know the DPRK is famous for rockets and air filters.
1

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