Thermal Systems Engineer in Phoenix

Job Description GTI is a contract manufacturing partner supporting customers in renewable energy, power, infrastructure, and industrial systems. We fabricate custom designed, purpose-built enclosures and skids for our customers and perform mechanical and electrical integration in-house, delivering a true turn‑key product to our customers. Our scope spans Engineering, prototype builds, through full production, requiring teams that can move fast, adapt, and execute with precision.

GTI Values:
Safety I Quality I Customer Obsession I Speed I Agility

GTI Energy is seeking a Senior Mechanical Engineer to lead mechanical and thermal system design for enclosed industrial products including BESS platforms, modular data centers, power skids, and integrated energy infrastructure. This role is responsible for designing cooling systems, airflow management strategies, enclosure integration, and mechanical assemblies that perform reliably under real‑world operating constraints.

This is not a traditional HVAC or commercial building engineering role. GTI is specifically seeking candidates with experience designing cooling systems for enclosed equipment and industrial systems where space limitations, airflow management, manufacturability, vibration, acoustics, serviceability, and environmental conditions must all be considered simultaneously.

The ideal Senior Mechanical Engineer has experience supporting products such as battery systems, power electronics, generator enclosures, modular data centers, industrial skids, switch gear systems, or other enclosed industrial equipment requiring engineered thermal management solutions.

• Design and integrate cooling systems for enclosed industrial equipment including BESS systems, modular data centers, power distribution equipment, and power platforms
• Size cooling systems based on actual equipment heat loads, thermal rejection requirements, and operating conditions
• Develop airflow strategies inside enclosed systems including ducting, circulation paths, pressure balancing intake/exhaust placement, and thermal zoning
• Design systems for worst‑case ambient conditions, elevated operating loads, and real‑world environmental constraints rather than nominal conditions only
• Select and integrate off‑the‑shelf cooling equipment including HVAC units, heat exchangers, fans, chillers, and thermal management components

• Own mechanical design from concept through production release including enclosure layouts, mounting systems, access requirements, structural interfaces, and equipment integration
• Develop 3D CAD models, assemblies, manufacturing drawings, and BOMs using Solid Works and related engineering tools
• Design for manufacturability, assembly efficiency, serviceability, and long‑term reliability
• Support integration of pumps, piping, cable routing, thermal barriers, and mechanical support systems
• Coordinate packaging constraints involving electrical systems, structural members, airflow, and maintenance access

• Perform thermal analysis, airflow modeling, and engineering calculations supporting cooling system performance
• Support CFD analysis and interpretation where applicable
• Validate mechanical and thermal performance through testing, prototype evaluation, and field feedback
• Participate in heat runs, system testing, troubleshooting, and performance optimization activities
• Ensure designs meet customer, regulatory, and operational requirements

• Partner with Electrical Engineering, Structural Engineering, Manufacturing Engineering, NPI, Quality, and Operations teams throughout product development lifecycle
• Collaborate closely with manufacturing teams to ensure designs align with fabrication, welding, assembly, and integration capabilities
• Support prototype builds, pilot programs, and production launch activities
• Work directly with Supply Chain and vendors on component selection, manufacturability, and technical problem solving

• Drive DFM…