Support the operation, inspection, troubleshooting, and maintenance of HVAC equipment, Building Automation Systems (BAS), Direct Digital Control (DDC) systems, steam and hot water systems, chillers, air handling units, geothermal heat pumps, and related energy management equipment. Complete scheduled preventive maintenance activities, inspect electrical connections, motors, bearings, belts, filters, refrigerant systems, pumps, valves, and safety devices, and ensure compliance with safety and regulatory requirements.