Sr. Mechanical Building Engineer - Critical Environment

JLL empowers you to shape a brighter way.

Our people at JLL are shaping the future of real estate for a better world by combining world class services, advisory and technology for our clients. We are committed to hiring the best, most talented people and empowering them to thrive, grow meaningful careers and to find a place where they belong. Whether you’ve got deep experience in commercial real estate, skilled trades or technology, or you’re looking to apply your relevant experience to a new industry, join our team as we help shape a brighter way forward.

As a Senior Mechanical Building Engineer at JLL, you will serve as the technical cornerstone for advanced mechanical systems that sustain today's most critical data center and facility environments. This senior-level role combines deep mechanical engineering expertise with hands-on operational leadership, positioning you as the go-to expert for complex HVAC systems, chillers, cooling infrastructure, and environmental control systems.

At JLL, we are collectively shaping a brighter way — for our clients, ourselves and our fellow employees, and your technical mastery will be essential in ensuring mission-critical uptime and operational excellence. You'll lead sophisticated troubleshooting initiatives, mentor junior engineering staff, and drive innovative solutions that optimize both performance and energy efficiency. We embrace more innovative ways of working and prioritize opportunities to strengthen and advance your career, providing you with the platform to apply cutting-edge mechanical engineering principles while managing large-scale infrastructure projects.

This role offers the perfect blend of technical challenge and leadership responsibility, allowing you to shape the future of critical facility operations while advancing your professional expertise.

Lead comprehensive operations and maintenance of critical mechanical infrastructure including HVAC systems, chillers, CRAC/CRAH units, cooling towers, and air handling systems

Oversee complex chilled water systems, pumps, valves, piping networks, and filtration systems to maintain optimal environmental conditions for mission-critical operations

Execute advanced diagnostics and root cause analysis on sophisticated mechanical equipment failures, implementing sustainable solutions

Apply mechanical engineering principles to design and implement cooling solutions optimized for high-density server environments and evolving technology demands

Serve as the primary escalation point for Level 1 and Level 2 mechanical issues requiring advanced technical expertise and critical problem-solving

Develop and execute comprehensive preventive maintenance schedules that ensure 100% uptime and peak performance across all mechanical infrastructure

Analyze mechanical system performance data and implement optimization strategies that reduce Power Usage Effectiveness and enhance sustainability

Mentor and guide junior mechanical technicians and engineers, fostering technical excellence and professional development within the team

Coordinate complex mechanical infrastructure projects including system upgrades, expansions, and integration of cutting-edge technologies

Minimum 5 years of hands-on technical experience in critical facility mechanical engineering with expertise in HVAC, plumbing, and production equipment

At least 3 years of specialized experience in data center or raised floor environments with complex cooling requirements

Advanced technical knowledge of CRAC/CRAH systems (Liebert preferred), chillers, and comprehensive cooling infrastructure operations

Current Universal EPA 608 Certification demonstrating expertise in refrigeration and environmental compliance

Strong analytical and problem-solving capabilities for diagnosing and resolving complex mechanical system challenges

Demonstrated leadership and mentoring experience with ability to guide technical teams and drive operational excellence

Excellent verbal and written communication skills for creating technical…