SEJOY: 1 DOE certified model
SEJOY has one air purifier basic model certified to DOE as of 2026-11-03, rated smoke CADR 47 cfm. It's the same unit as a model filed under 1 other brand. How its efficiency compares with its DOE class is below.
Source: DOE Compliance Certification Database (air purifiers), data as of 2026-11-03.
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Air purifiers
| # | Photo | Model | Labels | Smoke CADR, cfm | Room size | PM2.5 CADR | CADR/W | Brands | Amazon |
|---|---|---|---|---|---|---|---|---|---|
| 1 |  | SEJOYAC400filed as Purivortex KJ100F |
| 47cfm, 73 sq ft | 73 sq ft | 48 | 3.4 | 2 | Check price on Amazon |
How efficient is the SEJOY AC400?
SEJOY AC400 files CADR/W 3.4. The median among the 90 models in its DOE class (air purifiers, PM2.5 CADR 10 to 99 cfm) is 3.5, so it's below the median: higher than 43 of the 90.
A higher CADR/W means more clean air per watt.
Who makes SEJOY air purifiers?
DOE's database has no manufacturer field, so the evidence is whose model number each unit is filed under and which other brands file the same unit.
SEJOY shares its basic model with one other brand, Purivortex.
| Basic model | SEJOY model | Number belongs to | Brands |
|---|---|---|---|
| KJ100F | AC400 | No known prefix | 2 |
How much does a SEJOY air purifier cost to run?
For SEJOY AC400, DOE's record lists 68 kWh a year, the annual energy figure from DOE's test. That's about $12.35 a year.
At 18.16¢ per kWh, the US average residential price for August 2026 (EIA Electric Power Monthly, table 5.6.A). Worked out from the certified figures.
How does SEJOY AC400 compare with other brands?
Picked by rule from models with a matched listing, DOE data as of 2026-11-03.
- Within 20 cfm of its size, highest CADR/W: DREAME CVA10B, 54 cfm. Room size 84 sq ft, CADR/W 10.3: about 67% less power for the same clean air.
- Nearest size in its class with a higher CADR/W: Bionaire BAP9260, 46 cfm. Room size 71 sq ft, CADR/W 4.5: about 24% less power for the same clean air.
- Nearest bigger unit: Blueair 3131000100, 69 cfm. Room size 107 sq ft, CADR/W 8.
Questions about SEJOY
- Is SEJOY a good air purifier brand?
- Its one air purifier basic model, SEJOY AC400, certifies 47 cfm, and its CADR/W of 3.4 is higher than 43 of the 90 in its DOE class (air purifiers, PM2.5 CADR 10 to 99 cfm). It's the same unit as another brand's model. We don't test reliability, noise or build quality, so we can't rank brands on those. How we compare models.
- What room size are SEJOY air purifiers rated for?
- DOE's effective room size for SEJOY AC400 is 73 sq ft, from a certified smoke CADR 47 cfm. CADR and room size.
- Is SEJOY the same as Purivortex?
- For one unit, yes: both file it under the same DOE basic model (KJ100F). Compare the 2 brands of KJ100F.