We are seeking a licensed Professional Engineer (PE) in Mechanical Engineering to join our Chicago-based data center design and engineering team. The ideal candidate will bring strong technical expertise in HVAC, cooling systems, and mission-critical infrastructure to support the design, construction, and commissioning of large-scale data centers. This role will work cross-functionally with project managers, electrical engineers, contractors, and clients to deliver high-performance, efficient, and sustainable facilities.Key ResponsibilitiesLead mechanical engineering design for hyperscale and enterprise data center projects.Perform load calculations, equipment sizing, and system design for HVAC, chilled water, CRAC/CRAH, and cooling towers.Ensure designs meet local codes, ASHRAE, NFPA, and data center industry standards.Prepare and review construction documents, specifications, and technical reports.Collaborate with electrical and structural teams to ensure fully coordinated designs.Oversee mechanical system testing, commissioning, and troubleshooting.Manage vendor relationships, review submittals, and approve equipment selections.Provide engineering support through construction administration and site visits.Ensure all designs prioritize reliability, redundancy (N+1, 2N), and energy efficiency.Mentor junior engineers and support team development.QualificationsBachelor's degree in Mechanical Engineering (Master's preferred).Active PE license in Illinois required.8+ years of experience in mechanical engineering with at least 3 years focused on mission-critical/data center projects.Strong knowledge of HVAC design, chilled water systems, air handling units, and heat rejection systems.Experience with CFD modeling and energy efficiency analysis preferred.Proficient in Revit, AutoCAD, and mechanical load calculation tools.Excellent communication, client-facing, and project leadership skills.