The HVAC Senior Mechanical Engineer will be responsible for the complete engineering and design of HVAC, steam, and industrial process piping systems. This role involves hands-on technical work, project coordination, and field integration support to ensure system performance and installation quality. You will lead detailed system design efforts including load calculations, equipment selection, duct and piping layout and sizing, control sequences, and technical specifications. Your work will directly impact project bidding, permitting, construction execution, and commissioning. This is a high-visibility role that collaborates with project managers, estimators, and field operations to bring complex mechanical systems to life.