What type of system is commonly used for humidification in HVAC?

Ultra-sonic systems are commonly used for humidification in HVAC because they create a fine mist of water droplets through high-frequency vibrations. This method allows for precise control over humidity levels in a space, making it effective for maintaining comfort and preventing issues related to overly dry air. These systems are often favored for their energy efficiency and low maintenance requirements.

Desiccant systems are primarily used for dehumidification rather than humidification, as they absorb moisture from the air. Chilled water systems are focused on cooling rather than humidity management, and while they can indirectly affect humidity through temperature changes, they are not specifically designed for humidification. Free-standing units may provide humidification but are typically not integrated into central HVAC systems, limiting their effectiveness in larger or commercial HVAC applications.