Other common titles: Service Technician, Building Engineer, heating, ventilation, air conditioning, refrigeration, cool, heat, air handlers, VAV, split systems, RTU, roof top unit, refrigerant, walk in coolers, coils, commercial, building, facility, facilities, retail, high rise, building automation system, BAS, BMS. Operate, maintain, monitor, and perform preventive, predictive, and corrective maintenance on building equipment, which may include: mechanical/HVAC/plumbing systems, electrical/cabling, fire detection and suppression, life safety, lighting, temperature control systems, building management systems, and digital systems.