Overview

NES Fircroft are delighted to be partnering with a multidisciplinary Mission Critical practice of Consulting Engineers providing a full range of Mechanical, Electrical and Public Health design and offer specialist services such as Computational Fluid Dynamics (CFD) simulation, electrical network analysis and offer full REVIT BIM capabilities. They are looking for a Principal Mechanical Engineer – Data Design to join their team in London. The role will be on a 12-month contract and will require 3 days in their Finsbury office and 2 days remote per week.

Responsibilities

• Lead and assist with the mechanical design for data centre projects from concept through completion.
• Provide technical oversight on HVAC, cooling, ventilation, and building services engineering.
• Ensure designs meet uptime requirements (Tier I–IV standards), local building codes, ASHRAE guidelines, and client specifications.
• Collaborate with electrical, structural, and controls engineering teams to deliver fully integrated solutions.
• Drive innovation in cooling technologies, including liquid cooling, free cooling, and energy-efficient designs.
• Conduct feasibility studies, capacity planning, and system optimization for scalability and redundancy.
• Mentor and develop junior and mid-level engineers within the design team.
• Act as the primary technical point of contact for clients, contractors, and stakeholders.
• Review vendor and contractor submittals, ensuring compliance with design intent and project goals.
• Support commissioning teams to verify system performance and reliability.
• Contribute to sustainability initiatives and energy efficiency targets (PUE, WUE improvements).

Qualifications & Experience

• Bachelor’s or Master’s degree in Mechanical Engineering or related discipline.
• Chartered/Professional Engineer (CEng or equivalent).
• 12+ years’ experience in mechanical engineering, with significant experience in data centre design.
• Deep knowledge of HVAC, chilled water systems, CRAH/CRAC units, cooling towers, and advanced thermal management solutions.
• Proven expertise in mission-critical facility design and operations.
• Familiarity with ASHRAE TC 9.9, Uptime Institute standards, and local building codes.
• Strong project leadership and client-facing skills.
• Proficiency in design software (e.g., AutoCAD, Revit, IES, CFD modelling tools).
• Demonstrated success delivering large-scale, high-reliability infrastructure projects.

Key Competencies

• Strong leadership and mentoring skills.
• Excellent communication and stakeholder management.
• Innovative problem-solver with a focus on energy efficiency.
• Detail-oriented, with the ability to manage complex projects.
• Adaptable to evolving technologies in data centre cooling and sustainability.

With over 90 years' combined experience, NES Fircroft (NES) is proud to be the world\'s leading engineering staffing provider spanning the Oil & Gas, Power & Renewables, Chemicals, Construction & Infrastructure, Life Sciences, Mining and Manufacturing sectors worldwide. With more than 80 offices in 45 countries, we are able to provide our clients with the engineering and technical expertise they need, wherever and whenever it is needed. We offer contractors far more than a traditional recruitment service, supporting with everything from securing visas and work permits, to providing market-leading benefits packages and accommodation, ensuring they are safely and compliantly able to support our clients.