Honeywell HPA5100B Allergen Plus HEPA Air Purifier (900 sq ft)

The Honeywell HPA5100B is a full-size True HEPA + activated carbon air purifier designed for large rooms up to 900 sq ft. It delivers a CADR of 300+ (dust, tobacco smoke, pollen) and runs at 52–70 dB depending on fan speed, with a usable Turbo Clean mode for rapid dust clearance. The unit features three-stage filtration (pre-filter, True HEPA, carbon), operates at roughly 100W, and uses standard replacement filters (HEPA + carbon combo) at moderate cost (~$40–50 per cartridge, 6–12 month intervals). Smart features are minimal—no app, no air-quality sensor, manual speed control only. It is CARB-certified ozone-safe. Best for allergy and asthma sufferers in large bedrooms, living rooms, or basements who prioritize proven filtration over convenience; it's a no-frills workhorse popular in r/AirPurifiers and forums for its reliable motor and low maintenance. Loud on high speed; lacks the premium quiet or smart automation of category leaders.