Blueair Blue Pure 311i Max
AHAM verified
- Really cleans
- 431 sq ft40 m² 40 m²431 sq ft
- Box says
- 2,207 sq ft205 m² 5.1× overstated
- New filter
- 9 months
Winix · 9800
Winix 9800
Really cleansAHAM verified
513 sq ft47 m² 47 m²513 sq ft
At 4.8 air changes an hour with a 2.5 m ceiling
- Box says
- Also cleans rooms up to 2,506 sq ft in 1 hourAlso cleans rooms up to 2,506 sq ft in 1 hour (233 m²) 4.9× overstated
- New filter
- Every 3–12 months
See it on Amazon: Winix 9800Paid link
A large Winix tower with a verified CADR, air quality sensors and an app. Cleans a living room with a dining area.
Verdict
Who it's for
A big, capable tower for a living room with a dining area, verified by AHAM, with air quality sensors and app control. Its carbon filter needs changing more often than the HEPA filter. PlasmaWave can be switched off.
Good
- CADR verified by AHAM
- Air quality sensors and auto mode
- App control
Trade-offs
- Carbon filter needs changing every few months
- Has a PlasmaWave ionizer
- Large and heavy
Spec facts
Winix 9800 · 9800
- Really cleans
- 513 sq ft · 47 m²47 m² · 513 sq ftat 4.8 air changes an hour, 2.5 m ceiling
- Box claim
- Also cleans rooms up to 2,506 sq ft in 1 hourAlso cleans rooms up to 2,506 sq ft in 1 hour (233 m²)4.9× overstated
- Maker’s claim: Winix · checked 1 Nov 2026
- Filter
- Winix Filter A (115115)True HEPA (12 months) + activated carbon (3 months). Replace every 3–12 months
- Maker’s claim: Winix · checked 1 Nov 2026
Certified: measured in an independent lab for AHAM’s Verifide programme. Maker’s claim: the manufacturer’s own figure, not independently checked. Where figures come from
Running it
Filter and upkeep
- Replacement filter
- Winix Filter A (115115)
- Type
- True HEPA (12 months) + activated carbon (3 months)
- Replace every
- 3–12 months
A new filter every 3–12 months means 1–4 filters a year. Its parts wear out at different rates, as the type above says, so the range covers both.
We have no Amazon link for this filter: the maker's page in the sources sells or lists it.
Source: Maker’s claim, Winix, checked 1 Nov 2026
The box vs the maths
The box says 2,506 sq ft233 m². It really cleans 513 sq ft47 m².
To clean 2,506 sq ft233 m² it would only change the air in the room 1 time an hour. We size every purifier at 4.8 air changes an hour, the level AHAM's room-size guideline works out to.
Winix's figure is the room it can change the air of once an hour, and the wording says as much. That's a real number, but at one air change an hour smoke and pollen come back in nearly as fast as the purifier removes them.
573 m³/h smoke CADR ÷ (4.8 × 2.5 m ceiling) = 47.7 m² = 513.6 sq ft47.7 m²
Use the calculator for your exact room and ceiling, or read how we pick.
Drawn to scale: the box says “Also cleans rooms up to 2,506 sq ft in 1 hour”, the purifier really cleans 513 sq ft, 4.9 times less.Drawn to scale: the box says “Also cleans rooms up to 2,506 sq ft in 1 hour”, the purifier really cleans 47 m², 4.9 times less.
Room sizes
Which rooms it fits
It suits 269 sq ft25 m², 322 sq ft30 m² and 376 sq ft35 m² rooms best: there it has 34–88% more air than the room needs, so it needn't run flat out. At 430 sq ft40 m² it only just keeps up (17% to spare), so it would run near its top speed, usually its loudest (why we don’t list noise). In rooms of 215 sq ft20 m² or less it's more than twice the size needed; a smaller model does the job.
Under a 2.7 m ceiling it covers 475 sq ft, under 3 m 427 sq ftUnder a 2.7 m ceiling it covers 44 m², under 3 m 39 m², so with a 3 m ceiling it no longer covers 430 sq ft40 m² (why).
For a 538 sq ft room or bigger it's too small, although the box claims 2,506 sq ft: the For a 50 m² room or bigger it's too small, although the box claims 233 m²: the 538 sq ft50 m² page lists models that cover it. In an open-plan space, add up every area without a door between (how).
Alternatives
The Winix 9800 or one of these?
The certified models closest in size, and what is different about each, from the same kinds of source.
Cleans 431 sq ft, 82 sq ft lessCleans 40 m², 7 m² less. It has no ionizer. It has a different filter schedule (every 9 months). 10.6 cm shorter and 4.9 kg lighter.
Honeywell HPA300
AHAM verified
- Really cleans
- 457 sq ft42 m² 42 m²457 sq ft
- Box says
- 465 sq ft43 m² about right
- New filter
- 3–12 months
Cleans 457 sq ft, 56 sq ft lessCleans 42 m², 5 m² less. It has no air quality sensor or ionizer.
Levoit EverestAir-P
AHAM verified
- Really cleans
- 539 sq ft50 m² 50 m²539 sq ft
- Box says
- 2,635 sq ft245 m² 4.9× overstated
- New filter
- 12–15 months
Cleans 539 sq ft, 26 sq ft moreCleans 50 m², 3 m² more. It has no ionizer. It goes longer between filters (every 12–15 months). 0.9 kg heavier.
Sources
Where these numbers come from
- Certified AHAM Verifide directory: Winix 9800, C909 · AHAM Verifide
- Maker’s claim Winix 9800 product page and specifications · Winix
- Maker’s manual Winix 9800 user manual (PDF) · Winix
We don't test purifiers ourselves: every figure on this page is copied from these sources and was last checked on 1 Nov 2026. Spotted one that's wrong or out of date? Tell us and we'll fix it and change the date.