Coway Airmega 400S Smart Air Purifier with True HEPA Filter for Cleaner Air

Amazon Customer: I purchased this product because I moved into a loft building and the place was smelling a touch less than fresh. I’ve had the unit running for about 4 weeks now and I can notice a significant difference in the place. A fluke discovery I made this week and is what prompted me to write the review, was I fried some fish on the stove top and within 5 mins, the indication on the unit changed to a yellow orange colour to signify it has detected contaminates in the air. After about an hour and half, the indicator was back to green blue and you couldn’t smell a single odour from the dinner, absolutely amazing (Ive repeated this twice with alternate foods and same results).
*Sound is equivalent to a standard oscillating fan, not bad at all.
*Build quality - excellent
*User Friendly - excellent

Canada on Aug 14, 2023

Tom2154: Before we purchased the air purifier, we had to dust almost every day. Now it is about once a week so the unit is definitely taking the dust and dander particles out of the air. It works on the Smart mode, so we never have to adjust anything or worry about it working as it is needed.

We have this on the main floor of a 2-floor house. The main floor is about 1,000 sq. feet in an open arrangement of Kitchen, den living room and it does a great job in that amount of space.

The filter requires cleaning about every 4 weeks or so, but it will alert you when it needs to be cleaned with a vacuum. The main filter lasts approximately one year and Amazon offers a 2-pack generic replacement that is about forty five dollars for a 2-pack.

The app that comes with it is very unreliable and really doesn't do anything useful at all except alert you when the air quality is poor and when the filter needs to be cleaned/replaced. If you lose wifi and the purifier has to be manually reset to restore the wifi, then it will automatically start the "alert" times for filter cleaning and replacement to zero, so it is not measuring anything but a set the time until cleaning or replacement...

United States on Aug 02, 2023

Jess: Really quiet functioning and it monitors odours as well as air pollution. I need to attach it my app and then will have a full verdict works well.

Canada on Jul 22, 2023

Alex Diamantopulo: I bought this filter in 2021 and it is always on since then.
I am monitoring my air quality with a separate tool and I can see a huge change with this filter on 27/7.
I also like the remote control option, it works with Home Assistant.
My only comment to manufacturer: PLEASE stop forcing people to use cloud services. It would be great to have an option to set it up locally with Home Assistant, without using cloud services.

Canada on Jul 01, 2023

jean huot: Quiet, large and thick filters. Does not show exact ppm, but indicates good, moderate, unhealthy and very unhealthy. Fairly big unit compared to competition. Well built. Des not use bluetooth., but i guess can be monitored remotely via internet. Got it on sale, but would not pay full price. PreFilter is at 96% current state and hepa filter at 100%. Carbon filter integrated with hepa filter. Easy access to filters. Granular carbon filter; more efficient. Intelligent fan speed control increases speed when there is more pollution. Wish I had it last week when polution was at a high level indoor.

Canada on Jun 30, 2023

Zoe: I have been using this air purifier for a couple months now, it's very quiet, even on the highest setting I can barely hear it running, it has HEPA filters on both sides to intakes air on 2 sides, is nicer looking than many other other brands, the cord isn't your typical plastic rubber type, but a retro cloth looking cord which is a nice touch. The app seems a little spotty but the unit itself has been excellent.

While more expensive than other brands this unit seems far better made, and overall I would highly recommend this unit if your looking for an air purifier.

Canada on Jun 03, 2023

Self Analysis: The filter itself has provided phenomenal filtration for approx. 600 sq ft space. The circular LED particle display is very sensitive to report dust or humidity passing inside the sensor with different colors. The filters themselves are obviously made with the highest quality, and are multi-stage and readily suck up smoke, most smells and dust. The circular indicator goes yellow or red when it detects particles and gradually absorbs the particulates until the indicators returns to the reassuring "blue-green" color.

I bought this to combat smells migrating from a neighbor in the unit below. It does a valiant job. The neighbor is a formidable foe, however. So I don't fault the unit. The filters are quite expensive. The filter has last months so far, and the LED filter life indicator suggests it is half expended. I have cleaned the fine metal screens, running them under water to rinse off dust rather than letting it go airborne again. The clean-the-metal-screen indicator activates pretty often—about once a week—which is more than I would expect. It is not a big chore, but I didn't know I would have a job to do to maintain the filter, albeit minor. Air quality has been...

United States on May 15, 2023

kamiraakamiraa: First off this filter is very large and the filters within it are huge in comparison to other competitors (Detailing Honeywell AirGenius 4 / 5 , Honeywell HEPA HPA300, and Molekule below). Check out the overall measurements of the unit before ordering it - 15" by 15" by 23" tall.

First off, this purifier is BIG, and has TWO LARGE HEPA / Charcoal filters on each side. The HEPA will remove 99%+ of air contaminates and the Charcoal will scrub any smell. Do you have dogs or live in an area with bad air quality? Get this! The only downside is that the filters need to be replaced once a year and typically around $120 for the full set, you dispose the old ones. But when it comes to health . . . just do it. I had "Cleanable" filters in the past such as the Honeywell AirGenius 4 & 5 , let me say when you have to do it 4 times a year, I rather just pay $120 for the set. It typically takes 45 minutes each time to clean the AirGenius and about 4-5 hours to dry.

The Coway Airmega 400s purifier also has a fine mesh pre-filter on each side of the unit (before the main HEPA / Charcoal). It is VERY fine, and is meant to capture hair and other items (heavy dust). These do not need...

United States on Apr 23, 2019