Yes to both. PECOAir and PECOAir+ are designed to run continuously, and that’s how it works best.
Air doesn’t stay clean once you turn the purifier off. Dust, dander, pollen and VOCs are always entering a room, from people, pets, cooking, furniture and the outdoors, so a purifier that runs for an hour and stops is cleaning a room that immediately starts filling back up. Left on, it keeps the air at a steady baseline instead of chasing it.
Auto Protect makes this easy. The purifier stays at a quiet, low speed most of the day and only ramps up when its sensors detect a change, so running it around the clock doesn’t mean running it loud. In Sleep mode it’s quieter still. Power draw is modest, about $10 a month even at full speed and well under that in Auto Protect, and the Nidec brushless motor is designed for continuous duty.
The only reason to turn it off is if you’re leaving for an extended period. Otherwise, set it to Auto Protect and leave it.