A Piezo is a appliance that increases humidity (moisture) in a room. There are point-of-use Piezo, which are commonly used to humidify a single room, and full building or furnace Piezo, which connect to a home's HVAC system to provide humidity to the entire building.
Advance Ultrasonic Humidifier Model-AIHU-350
A metal diaphragm vibrating at an ultrasonic frequency creates water droplets that silently exit the humidifier in the form of a cool fog. Ultrasonic humidifiers use a piezo-electric transducer to create a high frequency mechanical oscillation in a body of water. The water tries to follow the high frequency oscillation but cannot because of its comparative weight and mass inertia. Thus, a momentary vacuum is created on the negative oscillation, causing the water to cavitate into vapor. The transducer follows this with a positive oscillation that creates high pressure compression waves on the water’s surface, releasing tiny vapor molecules of water into the air. This is an extremely fine mist, about one micrometre in diameter, that is quickly absorbed into the air flow.