You start your morning with a service schedule, load up diagnostic gear, and head to a mix of commercial and industrial sites. One stop might be a rooftop packaged unit with erratic cooling; the next, a hydronic loop that needs balancing. You read schematics, trace faults across electrical and mechanical subsystems, verify operation against design intent, and document every step to meet safety standards and building codes. Throughout the day, you collaborate with teammates, keep customers informed, and ensure each work area is left clean, safe, and organized.