The definition of a HVAC DDC<DDC (Direct Digital Control) system is a computerized system that controls the temperature, humidity, and air quality of a building or space. It is a type of building automation system that is designed to monitor and control the various aspects of a building’s environment, such as temperature, humidity, air quality, and energy efficiency. The system can be programmed to control the operation of HVAC equipment, lighting, and other building systems. It is a very efficient way to manage a building’s energy usage and to ensure that the occupants are comfortable. HVAC DDC<DDC systems are also used to monitor and control energy usage in order to reduce energy costs. They are also used to monitor and control air quality, which can help to reduce the spread of airborne diseases. In addition, they can be used to monitor and control the building’s water usage, which can help to reduce water costs. HVAC DDC<DDC systems are becoming increasingly popular in commercial and residential buildings, as they offer a number of benefits.