Product overview
Winix 5500-2: What to Know
The 5500-2 is AHAM-certified for a 360 sq ft room with CADR ratings of 232 (smoke), 243 (dust), and 246 (pollen). Filtration runs through four stages: a washable pre-filter, a washable AOC (activated oxygen catalyst) carbon filter, a True HEPA filter, and Winix's PlasmaWave technology, which uses a small electrical charge to generate hydroxyl ions rather than functioning as a conventional ionizer. The unit is CARB-certified, meaning independent testing found its ozone output below California's safety threshold, and PlasmaWave can be switched off separately if you'd rather run HEPA filtration alone.
Noise is the one area where this research turned up genuine, unresolved inconsistency. We were not able to access winixamerica.com directly during this research pass to confirm Winix's own published dB figures, and secondary sources disagree with each other: one independent breakdown lists roughly 40.6 dB at sleep rising to 66.4 dB at turbo, while other summaries cite a low-speed figure closer to 35 dB and a top-speed figure as high as 67.5 dB. Rather than pick one number and present it as settled, the honest takeaway is that this unit's noise range sits somewhere in the mid-30s to upper-60s dB depending on speed, and buyers sensitive to noise should verify the printed spec sheet or manual directly.
Because the pre-filter and AOC carbon filter are washable and reusable, the only recurring disposable cost is the True HEPA filter itself, which Winix rates for up to about 12 months of use, a genuinely lower long-term cost of ownership than fully-disposable-cartridge designs like the Levoit or Dyson in this comparison. Winix recommends washing the pre-filter every 2-3 weeks and the carbon filter roughly every 3 months to maintain performance.
One real limitation: the auto-mode air quality sensor detects odors only, not dust or pollen particulate levels, so auto mode may not ramp up fan speed in response to a purely particulate air-quality event even though the HEPA filter itself is fully capable of handling it. We were also unable to independently verify a current product photo for this exact listing during this research pass, so no image is shown here pending confirmation.
Key Listed Features
AHAM-verified CADR of 232 (smoke) / 243 (dust) / 246 (pollen) for a 360 sq ft rated room
4-stage filtration: washable pre-filter, washable AOC carbon filter, True HEPA, PlasmaWave
CARB-certified low-ozone ionization technology that can be toggled off independently
True HEPA filter rated for up to 12 months before replacement, with washable pre- and carbon filters reducing recurring cost
