Which acronym refers to the controls that automatically modulate HVAC equipment?

• A. System verification check
• B. Test and balance engineer
• C. Design intent document
• D. Automatic temperature controls

Answer: (D)

Automatic Temperature Controls are the systems that automatically modulate HVAC equipment to keep space conditions within the desired range. They use sensors to monitor temperature (and sometimes humidity or other factors), a controller to compare the sensed data to setpoints, and actuators that adjust components such as dampers, valves, fan speeds, and equipment staging. This closed-loop feedback lets the system continually fine-tune heating, cooling, and air when needed, delivering consistent comfort and often saving energy by avoiding unnecessary equipment runs.

Other options describe people, checks, or documents rather than the control system itself. A verification check is a commissioning step to confirm systems function, a test and balance engineer is a professional who performs testing and balancing, and a design intent document outlines goals and requirements rather than how the system automatically regulates conditions.