Tried and Tested: Dyson Big+Quiet Air Purifier review
Powerful enough to work in a 100 sqm space, this Dyson appliance has one “super impressive” new feature in particular hat makes it stand out.
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With the Dyson Big+Quiet Formaldehyde, you know what you’re getting: it is, indeed, both big and quiet. I’ve checked.
The only thing the name doesn’t specify is that it’s an air purifier. You would be forgiven for not getting that by looking at it, because it kind of looks like a pacifist dalek from Doctor Who wearing a cone so it doesn’t lick its stitches.
But, that cone is more than a mere Elizabethan collar, or what a vet would give your dog after surgery.
It’s actually employing a kind of engineering witchcraft to exploit loopholes in the laws of physics.
It uses “Cone Aerodynamics”, which harnesses the Coanda Effect to “merge two streams of air over a smooth surface”, which then allows the clean air to be thrown further, more quietly. Basically, the fan throws two beams of air over a curved surface (the cone) so then they travel further when they meet back in the middle.
Most normal air purifiers need to be placed in the centre of the room to circulate air, and need to have a high fan speed to do it efficiently anywhere larger than the smallest bedroom.
The thing is, though, that most people don’t actually place their air purifiers in the centre of the room, because they are generally pretty ugly white monoliths and that’s not how interior design or life work.
The Dyson Big+Quiet Formaldehyde is designed to be able to be placed in the corner of a room and purify up to a 100 sqm area.
This is great for living rooms, businesses, or aggressively open plan living spaces.
I’ve been using the Dyson Big+Quiet for a little over a week, and I’ve been really impressed with how it’s performed so far.
In This Article
Dyson Big+Quiet Formaldehyde verdict
SENSORS AND FILTRATION
Any good air purifier will purify most of the appropriately sized contaminants from the air, regardless of how specific the sensors get.
But I like that the Big+Quiet has so many sensors for a couple of reasons: 1. I am a nerd and I like to be able to see just how messed up the air in my home is.
2. I leave my purifier on auto, so the more its aware of what’s going on in my air, the more it knows when to turn up the fans if things start to get weird.
In the MyDyson app, the Big+Quiet gives information on the general air quality, humidity, VOCs (volatile organic compounds, gasses or fumes from things like cleaning supplies), PM2.5 (tiny particles from things like smoke or pollution), PM10 (particles from dust or smoke), HCHO (formaldehyde), and temperature.
In my tests, the Big+Quiet on auto mode has been great at picking up gentle pollutants within a metre or two of the unit, but needed the fan turned up to be able to detect things further away in a timely manner, which makes sense.
There are two consumer models of the Dyson Big+Quiet Formaldehyde. Both will do a good job, but the gold Big+Quiet Formaldehyde purifier you can only get from the Dyson website (as opposed to the blue/silver one from other retailers) also has a CO2 sensor. Carbon dioxide sensors are super helpful because they tell you how good the ventilation and air circulation in your room is. This is different to a carbon monoxide sensor, which would tell you if you’ve got a gas leak. You need a separate one of those.
Both machines are fully sealed, so no particles can escape the HEPA H13 filter. Some brands test and seal just the HEPA filter, and it’s always appreciated when a company goes the extra (more useful) step of sealing the whole thing.
TESTING AND COMPARISONS
Big air purifiers have been making claims about big rooms for years, with mixed results. There are a few air purifiers I really like for larger rooms, like living rooms. The Samsung Air Purifier AX60 is the one that I’ve been using in my living room for a while (with the Dyson Purifier Hot+Cool in the bedrooms), and I also really like the TruSens purifiers because of their secondary air sensor to make sure the whole room’s air is cleaned.
While I fully acknowledge that I do not have a closed lab with controlled conditions, and it is almost impossible to standardise air quality tests without one, in my home tests, I’ve found that the Big+Quiet runs more quietly and efficiently than the other large purifiers I’ve tried.
It doesn’t have the same extra, external sensors as the TruSens to know what’s happening in other parts of the room, so it can be slower to react to, say, candles on the dining table.
But it appears to pick up on particles from cooking faster, and brings the air back down to acceptable levels of PM2.5 up to an hour faster than the Samsung model.
This is partially because the Big+Quiet is so much larger than the Samsung (both of which are larger than my model of the TruSens), but also because it is able to throw that clean air a bit more aggressively.
It emphasises the importance of getting an air purifier at least one size larger than you think you’ll need, but also the effectiveness of the Coanda Effect.
Comparing the fan sounds side-by-side, it’s incredible how much quieter the Big+Quiet is than the other purifiers. Super impressive. Much more comfortable to sleep near, and less intrusive in day-to-day use.
BREEZE MODE
The weirdest, and also most delightful, feature of the Dyson Big+Quiet is breeze mode. It’s delightful, because it mimics the feeling of a nice breeze on a spring day. While the Big+Quiet isn’t a fan like the Pure Hot+Cool, it is still blowing air into your room. On breeze mode on 10, it feels like an enthusiastic breeze rather than standing in a wind machine. It’s just a nicer experience.
The thing that makes it weird is that some Dyson engineer spent a year collecting thousands of hours of data on breezes, and then had to use maths to work out how to make a purifier mimic a breeze. We all know what a breeze feels like, and the ineffable qualities that separate it from other forms of air movement. Yet this guy actually cracked the code on what makes it feel like a breeze, because they actually pulled it off.
Weird, but nice.
DYSON BIG+QUIET FORMALDEHYDE VEDICT
There is no going around the fact that this is a very expensive air purifier. It’s not the most expensive purifier on the market, but it is up there at $1499 and $1599 (for the Dyson direct version). But it’s also very, very, very good. I’ve been road testing air purifiers for many years, and this is the best I’ve tried.
So, if you’re wanting an air purifier for a room larger than a 3mx3m bedroom, and want one that isn’t too loud, the Dyson Big+Quiet Formaldehyde absolutely lives up to its name and brand reputation.
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