Why it matters
The Blueair Blue Pure 511i Max is a HEPA room unit air purifier that its maker rates for 237 sq ft.
At the usual 4.8 air changes an hour and an 8-foot ceiling, a 237-square-foot rating implies about 152 cubic feet of clean air a minute. In a 12-by-15-foot bedroom that would turn the air over roughly 6 times an hour.
Filtration: HEPASilent. Quietest setting, per the maker: 48 dB. Power draw: 20 watts.
Price-wise it sat in the cheapest third of the 74 hepa room unit models we cover when we checked; the button shows today's price.
It qualifies for our lists Best Air Purifiers for Allergies, Best Air Purifiers for Apartments and Dorms, Best Air Purifiers for Home Offices, where it is ranked against every model that meets the same rule.
Its rated room size of 237 square feet is one of the smallest ratings we cover: 12 of the 152 purifiers with a stated figure come in lower, and the range runs from 62 square feet to 4,800 square feet.
Compared with the Blueair Blue Pure 411i+ Max: rated room size 237 sq ft here vs 259 sq ft.
The listing gives a weight of 4.2 lb.
Warranty, per the maker: 1 year.
Who it's for, and who should skip it
Good fit if
- Rooms up to about 237 sq ft
- Allergy season
Look elsewhere if
- Whole-home filtration on its own
- Removing gases without a substantial carbon stage
Pros and cons
Pros
- Rated for 237 sq ft
- Low setting 48 dB
- 20 watts draw
Cons
- Filters are an ongoing cost
- Size to the room at 4.8 air changes per hour
Limitations to weigh
- Specifications are the maker's or seller's own figures; check fit against your equipment's model number and the actual size.
Specifications
The bracket shows where each figure comes from.
| Price | $139.99 | Maker |
|---|---|---|
| Warranty | 1 years | Maker |
| Product weight | 4.2 lb | Maker |
| Room coverage | 237 sq ft | Maker |
| Filter type | HEPASilent | Maker |
| Noise (seller) | 48 dB | Retailer |
| Wattage | 20 watts | Retailer |
Alternatives worth comparing
More air purifiers we cover
- Shark Clean Sense Max HP201 Air Purifier
- IQAir GC MultiGas XE Air Purifier
- Coway Airmega Mighty2 $269.99
- AirDoctor AD5500 $999
- PuroAir Lite HEPA Air Purifier $69.97
All air purifiers, compared in one table · Every Blueair product we cover
Final verdict
A well-matched choice for rooms up to about 237 sq ft. Confirm the model it fits before ordering.
Where to buy
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