Best Coway Airmega for an Open-Plan Floor or Whole Apartment During a Smoke Event
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The short answer: The Airmega 350 is the best overall pick: it delivers the highest CADR in the family at 352 and covers 2,640 sq ft for $339, the lowest price here. Step up to the Airmega 400 or 400S only if you want the largest listed coverage of 3,120 sq ft, and choose the 400S over the 400 only if its feature set matters more to you than the $100 difference.
- Best overall: Airmega 350 — Highest CADR in the family at 352 with 2,640 sq ft coverage, and at $339 it is the lowest-priced model here. See price at cowaymega.com
- Best compact: Airmega 300 — At 13.6 x 21.2 x 13.6 in and 21.4 lb it is the smallest and lightest of the 300/400 series, with 285 CADR and 2,512 sq ft coverage for $549. See price at cowaymega.com
- Best premium: Airmega 400 — Matches the 400S on 328 CADR and 3,120 sq ft coverage but costs $100 less at $649. See price at cowaymega.com
- Best for large open plan: Airmega 400S — Same 328 CADR and 3,120 sq ft coverage as the 400, with a 1-2 timer, at $749. See price at cowaymega.com
| Product | cadr | coverage sqft | noise db | filter life | dimensions | timer | Price now | 90-day low | Rating | |
|---|---|---|---|---|---|---|---|---|---|---|
| Airmega 300 | 285 | 2512 sq ft | 22 dB | Max2 Filter Set | 13.6 x 21.2 x 13.6 in | 1 4 | $549.00 | — | — | cowaymega.com |
| Airmega 350 | 352 | 2640 sq ft | 21.5 dB | 3-in-1 Custom Filter Set | 12 x 12 x 23 in | 1 4 | $339.00 | — | — | cowaymega.com |
| Airmega 400 | 328 | 3120 sq ft | 22 dB | Max2 Filter Set | 14.8 x 22.8 x 14.8 in | 1 4 | $649.00 | — | — | cowaymega.com |
| Airmega 400S | 328 | 3120 sq ft | 22 dB | Max2 Filter Set | 14.8 x 22.8 x 14.8 in | 1 2 | $749.00 | — | — | cowaymega.com |
Airmega 300
Pros
- CADR of 285 with coverage rated up to 2,512 sq ft, suited to an open-plan floor or whole apartment
- Quiet operation at 22 dB, among the lowest noise figures in the lineup
- Runs at 57 W, less power draw than the Airmega 400 (66 W) and 400S
- Costs $100.00 less than the Airmega 400 and $200.00 less than the Airmega 400S
Cons
- At $549.00 it costs $210.00 more than the Airmega 350, which has a higher CADR of 352 and larger 2,640 sq ft coverage
- Lower CADR (285) and smaller coverage (2,512 sq ft) than the Airmega 350, 400 and 400S
Who it's for: Someone who wants a quiet, lower-power purifier for an open-plan floor or whole apartment and will trade some cleaning capacity to pay less than the 400 and 400S.
Airmega 350
Pros
- 352 CADR is the highest in the Airmega 300/400 series
- 2640 sq ft coverage suits an open-plan floor or whole apartment
- 21.5 dB is the quietest of the series
- $339.00 is $210.00 less than the Airmega 300 and $310.00 less than the Airmega 400
Cons
- 62 W draw is higher than the Airmega 300's 57 W
- 3-in-1 Custom Filter Set rather than the Max2 Filter Set used by the 300, 400 and 400S
Who it's for: Anyone wanting the strongest, quietest and least expensive air cleaning for a large open-plan space during a smoke event.
Airmega 400
Pros
- 3120 sq ft coverage is the largest in the Airmega 300/400 series, suited to an open-plan floor or whole apartment
- CADR of 328 with a Max2 Filter Set
- Runs at 22 dB, quiet for its size
- Costs $100.00 less than the Airmega 400S
Cons
- At $649.00 it costs $100.00 more than the Airmega 300 and $310.00 more than the Airmega 350
- 24.7 lb and 14.8 x 22.8 x 14.8 in, the heaviest and bulkiest of the 300/400 models
- 66 W power draw is the highest in the series
Who it's for: Buyers who need maximum coverage for an open-plan floor or whole apartment and will pay more for it.
Airmega 400S
Pros
- 3120 sq ft coverage and 328 CADR handle open-plan floors and whole apartments during smoke events
- 22 dB noise rating is quiet enough to run continuously
- Max2 Filter Set filter life
- $100.00 more than the Airmega 400, which shares the same 328 CADR, 3120 sq ft coverage and 22 dB noise rating
Cons
- $749.00 is the highest current price in the series, $410.00 more than the Airmega 350
- 1-2 timer settings, fewer than the 1-4 range on the Airmega 300, 350 and 400
- 24.7 lb is the heaviest unit in the series
Who it's for: Buyers who need maximum 3120 sq ft coverage for an open-plan home or whole apartment during a smoke event and will pay the series' top price.
How we chose
How we chose: We lined up the four Airmega 300-series and 400-series models and compared the numbers that matter for one purifier running on an open-plan floor or through a smoke event: CADR, listed coverage, dimensions, weight, noise, power draw and current price.
The Airmega 350 has the highest CADR in the family at 352 and covers 2,640 sq ft, in a 12 x 12 x 23 in body weighing 17.2 lb, at 21.5 dB and 62 W, for $339. The Airmega 300 is $210.00 more at $549.00, with a CADR of 285 and 2,512 sq ft of coverage. The Airmega 400 and 400S both list a CADR of 328 and the largest coverage here at 3,120 sq ft, in a 14.8 x 22.8 x 14.8 in body weighing 24.7 lb, at 22 dB; the 400 draws 66 W and costs $649.00, and the 400S costs $749.00, which is $100.00 more than the 400.
Who should skip these
If your room is smaller than the coverage these units are rated for, you may be buying more purifier than you need. The Airmega 300 is rated for 2,512 sq ft, the Airmega 350 for 2,640 sq ft, and the Airmega 400 and 400S for 3,120 sq ft each. A single bedroom or a small living room will not use that capacity.
Weight is the other reason to look elsewhere. The Airmega 350 is the lightest here at 17.2 lb, and the Airmega 300 is 21.4 lb. The Airmega 400 and 400S are both 24.7 lb, which matters if you move a unit between rooms or carry it up stairs.
Price is worth weighing too. The Airmega 350 is $339, the Airmega 300 is $549, the Airmega 400 is $649, and the Airmega 400S is $749. The Airmega 350 costs $310.00 less than the Airmega 400 and $410.00 less than the Airmega 400S.
How to choose the right one
Start with CADR and coverage. The Airmega 350 has a CADR of 352 and covers 2,640 sq ft. The Airmega 300 has a CADR of 285 and covers 2,512 sq ft. The Airmega 400 and 400S each have a CADR of 328 and the largest listed coverage at 3,120 sq ft. If your room is smaller, the 300 or 350 will do; if you need the most coverage listed here, look at the 400 or 400S.
Then weigh the price gaps. The Airmega 350 is $339.00, and the Airmega 300 costs $210.00 more than the 350. The Airmega 400 costs $100.00 more than the 300, and the Airmega 400S costs $100.00 more than the 400. Put another way, the 400 costs $310.00 more than the 350, and the 400S costs $410.00 more than the 350.
The 400 and 400S share the same CADR, coverage, dimensions, filter set, noise rating and weight. The 400S costs $100.00 more than the 400, so that gap comes down to whether its feature set matters to you.
Questions readers ask
Which model covers the largest space?
The Airmega 400 and 400S both list 3120 sq ft of coverage, the most in this family; the Airmega 350 covers 2640 sq ft and the Airmega 300 covers 2512 sq ft.
Which is the quietest?
The Airmega 350 is rated at 21.5 dB, slightly quieter than the 300, 400 and 400S at 22 dB.
How much more does the Airmega 400 cost than the 350?
The Airmega 400 costs $310.00 more than the Airmega 350, and the 400S costs $410.00 more than the 350.
What is the price difference between the 400 and the 400S?
The Airmega 400S costs $100.00 more than the Airmega 400.
Which model has the highest CADR?
The Airmega 350 has the highest CADR at 352, ahead of the 400 and 400S at 328 and the 300 at 285.
Update history
- — First published
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