“…Energy use from heating, ventilation, air conditioning, and refrigeration systems (HVAC&R) to offset the heating and cooling load and provide a proper indoor environment for occupants constitutes a large portion of the total energy consumed in buildings [1,2]. Although there have been many studies on the optimal control strategies of air-conditioning systems aiming at energy conservation [3,4], issues, including a problematic or inferior control sequence and set points, equipment performance degradation, and various faults that occur in HVAC&R and building energy systems, further increase the energy use or lead to undesired indoor environmental quality.…”