Our best bang for the buck unit for large spaces.  Multi-stage filtration  plus high-output plasma generator.
ImmuneAir Revolution (IA-S-3) is designed to accommodate room sizes up to 1050 sq. ft.  700 CFM air circulation will treat the air in a 1050 sq.ft. room every 12 minutes.
3 Stage Filtration System: (Activated Carbon, True HEPA, and Cold Catalyst)
High performance plasma generator makes 50 Million Ions/cubic cm. to recreate the healthy air of a mountain forest indoors and purify the air in the room of viruses, bacteria, and many pollutants by attacking them at the molecular level.
Captures and reduces up to 99% of particles 0.3 microns in the air, including pollen, pollutants and other allergens. It also reduces volatile organic compounds and reduces odor.
Internal UV-C light further sterilizes the air, killing bacteria and virues.
ImmuneAir Midi pollution sensor communicates indoor air quality in real-time. The brightly colored LED lets you know how clean or dirty your indoor air is every minute of the day. And it features a timer, and filter lifetime indicator.
Constantly-variable fan speeds plus auto mode which automatically optimizes the speed setting based on the level of indoor air quality. Whisper quite 35db Sleep Mode. 
Timer feature allows the machine to run 1-4 hours before automatically powering off.
Filter replacement indicator checks to let users be aware of when to wash or replace the filter.
65 W power consumption and quiet operation with noise level ranging from 35 dB to 62 dB.
Can be controlled using touch screen, included remote control, or WiFi phone app.
Limited manufacturer's warranty covers any internal/functional parts for 2 years Filters are excluded.