Coway Airmega 350 air purifier review: powerful air purification for large rooms
Welcome to the T3 review of the Coway Airmega 350, a powerful and efficient air purifier for large rooms and open plan spaces.
If you’re in the market for the best air purifier that can service rooms up to 185.5m², the highly efficient Coway Airmega 350 is a highly recommended contender.
I’ve been testing this model for the past week and I’m very impressed with how well it reacts to airborne contaminants and how well it clears a large living room of incense smoke. It’s also one of the quietest models I’ve tested so far. Here is my Coway Airmega 350 review.
Coway Airmega 350 Review: Price and Availability
If you live in the UK, buy the Coway Airmega 350 direct from Conway for the discounted price of £264.99 or visit Amazon where it sells for an RRP of £299.99.
Do you live in the US? Head over to the Coway website where the Airmega 350 is going for $267. Or, try Amazon, where it sells for the same price.
Coway Airmega 350 Review: Design and Features
(Image credit: Future)
I will admit that I have not reviewed anything of the South Korean Coway brand in the past, but thanks to the evidence of the performance of this moving air purifier, a few recommendations from expert reviews and, above all, the Red Dot Award in 2025 for innovation, I am happy to welcome the brand into my home.
At first, I thought the Airmega 350 might be just another bandwagon-eqsue model in a sea of air purifiers. But I was wrong because the Airmega 350 has turned out to be one of the best air purifiers for large rooms that I have come across so far.
At 59.1cm long and 30.5cm wide, the cylindrical Airmega 350 is larger than other models I’ve reviewed, and it’s designed for large rooms up to 185.5m² (that’s a room measuring 13.62m long and wide).
Although it is large in body, I have to say that I am taken by its clean white lines, hidden filter door and attractive, bright, white interface. According to the Coway website, this joint should remain dust free and I’m inclined to agree because I have the dustiest house in Oxfordshire and I’ve been impressed with how dusty it’s been over the last five days.
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The interface itself sports a range of functions and information. Starting on the left, the Mode setting offers four different fan speeds: Auto, Sleep, Turbo and Eco. Auto is what it says and makes full use of the unit’s excellent – and very sensitive – sensor, which increases fan speed when more dirt is detected. When this happens, the circular light around the interface glows in several different colors – blue in rest mode, green when something is detected, yellow when the air is polluted and red when the sensor detects high levels of pollution such as smoke from a cigarette or a wood burner.
Sleep mode, on the other hand, slows down the fans all the time making them almost inaudible, even from a few feet away; Eco, too, is a bit quieter while Turbo – the most powerful setting – is, in fact, at the lower end of the scale but not as deafening as you might think, because, overall, this is one of the quietest air purifiers I’ve ever tested. The last three functions include fan speed (three settings), light on/off switch, timer (1, 4 and 8 hours) and information reminder when the filter needs to be changed.
So what is the baby elephant in the room? Well, it’s sad to say, but this particular model doesn’t have WiFi capabilities and that means it can’t be controlled using your phone. While it’s not the end of the world, I consider the lack of any app a missed opportunity, especially given that other models in the Coway range can be used with a phone.
From a disturbing point of view, it means that you cannot remotely view any of the air purifier’s statistics, make any changes to the fan’s mode and speed and, perhaps most importantly, turn it off using your phone if you suddenly remember that you left the Airmega 350 running while you were at the airport preparing for a three-week vacation.
Given the size of this unit, it should come as no surprise that the filter itself is 31cm x 26cm. Plus, I think it should take home the Best Filter Color of the Year award for its brilliant green and black glow. Shame you’ll only see it when you first take the box out and when you replace it after a year or so.
(Image credit: Future)
Importantly, the Airmega 350 filter looks extremely well designed and has the level of build quality you usually see from Dyson, Phillips or Blueair. The 3-stage filter itself is of the HEPA variety with a built-in filter and an Active Carbon filter to capture the required 99.99% of air pollutants, including dust and odors. According to statistics, the Airmega 350 delivers a CADR (Clean Air Delivery Rate) of 713.6 m³/h. This figure is considered very good by people in the know and shows that the Airmega 350 is powerful enough for large rooms, open-plan living spaces and small offices.
Of course, one of the biggest problems when buying an air purifier from anyone other than the big players like Phillips, Blueair or Dyson is the availability of air filters, especially a year or so after purchasing the unit. I have reviewed a few small brands’ supplies in the past and noticed that their filters were no longer available, due to sold stock, the company no longer supports that particular product or the company is going out of business.
In this regard, it is reassuring to note that Coway has an established base in the UK, serving as part of its European expansion with a dedicated Coway UK website and a respectable presence on Amazon. For the record, the new Airmega 350 filter on Amazon is on sale for a reasonable £69.99. I should also add that, as I write, the Airmega 350 filter is not currently available on Coway’s UK website although I’m told it will be soon.
Coway Airmega 350 Review: Performance
(Image credit: Future)
The first thing that strikes you when you open this thing is how quiet it is when it’s just moving. Granted, the noise gets louder when the sensor detects high levels of pollution but this goes down once the air is cleaned, usually within a few minutes.
Worst of all, the sound produced by the fan is of low frequency – like the MeacoFan 1056 – so you don’t have to put up with the harmonic sound that always collides with other high frequencies from the average TV. That means you can continue watching “The Night Manager” with minimal background noise like I did.
I tested this unit using a Palo Santo incense stick and was very impressed. First, the Airmega 350 sensor is very sensitive so it doesn’t take much to kick it into gear. If there is only a small amount of dirt around it, it will usually run at half speed. But if the sensor detects anything like cigarettes or wood burner smoke nearby, the top circular light starts flashing red and the fan switches to high gear, where it stays that way for a minute or two before switching back on after the air is cleared.
(Image credit: Future)
This model has excellent suction power and I noticed this when it started to draw incense smoke from about four meters away. When I set the unit up in the middle of my living room it blows a lot of incense smoke, it takes less than a minute for the sensor to detect it and another eight minutes for the filter to fully remove the air.
I also did a smell test – using both tobacco and incense smoke – with my face straight up. I wanted to see if I could smell the residual smell of their smoke. The cigar test was 100% successful with no tobacco smoke smell at all but, as I expected due to the sweet smell of Palo Santo wood smoke, I could smell the wonderful aroma of it.
In conclusion, I am very impressed with this unit. It’s powerful enough for large rooms, it’s quieter than others I’ve tested and it works wonderfully, too. I just wish it came with the convenience of WiFi.
Coway Airmega 350 Review: Verdict
(Image credit: Future)
With its large HEPA and carbon filtration system and highly responsive sensor, the Coway Airmega 350 brings powerful and reliable air purification to large rooms. It is really quiet during daily use and reacts quickly to smoke and allergens, making it ideal for people with allergies, pet owners and smokers. Although its lack of WiFi connectivity and current filter costs limit its value a smidgen, this is a reliable, high-performance purifier that is truly impressive.
