What is the term for a diffuser system that conveys and diffuses air into a space under positive pressure?

The correct term for a diffuser system that conveys and diffuses air into a space under positive pressure is "Air distribution system." This terminology specifically refers to the entire system designed to transport air from a central unit, such as an air handling unit, and distribute it throughout a space.

In this context, an air distribution system is characterized by its components, such as ducts and diffusers, which work together to ensure that conditioned air is delivered effectively and evenly throughout the environment, creating a comfortable and controlled atmosphere. When the system operates under positive pressure, it signifies that the air pressure inside the space is higher than the pressure outside, which helps prevent unwanted infiltration of unconditioned air and ensures efficient air circulation.

Understanding the role of an air distribution system is crucial in HVAC design and operation, as it impacts energy efficiency, thermal comfort, and indoor air quality.