Abstract: A heating ventilation and air conditioning (HVAC) system includes an air handling unit having an air handling unit outlet, and at least one zone having an inlet and an outlet. The at least one zone is operably coupled to the air handling unit outlet. A return air duct fluidly connecting the outlet to the air handling unit and at least one sterilization system arranged within the return air duct at or directly downstream from the outlet. At least one indoor air quality sensor operable to monitor an indoor air quality within the at least one zone. A controller is operably coupled to the at least one indoor air quality sensor and the at least one sterilization system. The controller is configured to operate the at least one sterilization system when the indoor air quality within the at least one zone exceeds an allowable threshold.

Abstract: A system, for measurement of temperatures and detection of faults of parallel transformers in a DDC enclosure, that includes a first transformer and a second transformer arranged in a parallel configuration that deliver power to components of a building management system (BMS). The system also includes a direct digital control (DDC) circuit that controls power delivered through the first and the second transformers to the components of the building management system (BMS). The system further includes a first temperature sensor, operationally connected to the DDC circuit, which measures the temperature of the first transformer. Furthermore, the system includes a second temperature sensor, operationally connected to the DDC circuit, which measures the temperature of the second transformer. The DDC circuit determines a difference between the first temperature and the second temperature to predict a fault in the first transformer or the second transformer.