Why it matters
The AirDoctor AD4000 is a large-room / whole-floor air purifier that its maker rates for 694 sq ft, with a smoke CADR of 370 CFM.
At the usual 4.8 air changes an hour and an 8-foot ceiling, a 694-square-foot rating implies about 444 cubic feet of clean air a minute. In a 12-by-15-foot bedroom that would turn the air over roughly 19 times an hour.
Filtration: UltraHEPA.
Price-wise it sat in the middle third of the 57 large-room / whole-floor 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 Wildfire Smoke, Best Air Purifiers for Kitchens, where it is ranked against every model that meets the same rule.
Its rated room size of 694 square feet is below the middle of the range we cover: 51 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 AirDoctor AD1500: rated room size 694 sq ft here vs 320 sq ft; smoke CADR 370 CFM here vs 170 CFM.
The listing gives a weight of 15.8 lbs.
Who it's for, and who should skip it
Good fit if
- Rooms up to about 694 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 694 sq ft
- Smoke CADR 370 CFM
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 | $679 | Maker |
|---|---|---|
| Product weight | 15.8 lbs | Maker |
| Room coverage | 694 sq ft | Maker |
| CADR (smoke) | 370 CFM | Maker |
| Filter type | UltraHEPA | Maker |
| Replacement interval | every 6 months | Maker |
Alternatives worth comparing
More air purifiers we cover
- Blueair ComfortPure 3-in-1 T20i Air Purifier $599.99
- Winix C545 Air Purifier
- PuroAir 130i Smart HEPA Air Purifier $129.99
- Carrier PGAPXCAR1625 Air Purifier
- Airpura UV714 Air Purifier
All air purifiers, compared in one table · Every AirDoctor product we cover
Final verdict
A well-matched choice for rooms up to about 694 sq ft. Confirm the model it fits before ordering.
Where to buy
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