Mechanical Engineer - Mission Critical

Harley Ellis Devereaux • Los Angeles, CA

1d • Hybrid

About The Position

HED is seeking an experienced Mechanical Engineer to serve as a technical expert and design leader on major and complex mission-critical projects. The role leads the development of high-performance, integrated mechanical engineering solutions, sets standards for technical execution and quality assurance, and coordinates across disciplines. The engineer operates with autonomy, owns major portions of project design delivery, mentors cross-functional teams, represents the firm in client relationships, and guides engineering strategy, practice-wide standards, and design innovation.

The position leads mechanical design from early concept through construction administration, contributes to client and project planning, and supports technical excellence throughout project delivery. Mission-critical work includes data-center HVAC systems, equipment and load sizing, CFD report interpretation, efficiency requirements, redundancy and tier considerations, and master planning for future buildings and utility impacts. The role uses a hybrid work model, combining work from home with regular in-office days, in a professional open-space office environment. Applicants must be located in the US or Canada.

Requirements

• Bachelor's degree in Mechanical Engineering or equivalent.
• Professional Engineer (P.E.) licensure.
• Understanding of project financial status, project cost-budget development, client relationship value, and delivering projects with a focus on quality.
• Written and verbal communication skills commensurate with the position.
• Strong organizational skills.
• Revit experience.
• Computer experience, including word processing, spreadsheet use or creation, and email.
• Detail-oriented, self-motivated, enthusiastic, flexible, and curious approach.
• Ability to work well with others under deadline situations.
• Must be located in the US or Canada.

Nice To Haves

• 10+ years in the AEC industry preferred.

Responsibilities

• Lead design and documentation of complex mechanical systems, including HVAC, plumbing, and/or fire protection, with minimal oversight.
• Validate and approve mechanical engineering calculations, including refrigerant concentration limits, plumbing system sizing, and equipment sizing, and integrate results into system design.
• Oversee setup of mechanical Revit models, including views, sheet organization, system browser strategies, and annotation standards.
• Resolve interdisciplinary system conflicts in collaboration with architectural, structural, and civil teams.
• Serve as the primary mechanical technical contact for internal and external project teams.
• Review and approve mechanical submittals, RFIs, and substitutions, coordinating detailed responses with the broader team.
• Conduct site visits, field verification, and punch walks, and prepare professional mechanical field reports.
• Provide mechanical design leadership from concept through construction administration, informing system selection, performance targets, and documentation strategy.
• Guide QAQC reviews for mechanical deliverables and assist with project-specific mechanical quality plans.
• Mentor junior engineers and mechanical designers through delegation, technical feedback, and one-on-one coaching.
• Participate in mechanical-scope fee development, project scoping, and resource planning for proposals.
• Lead internal and external project meetings, presenting mechanical system concepts, decisions, and trade-offs.
• Apply knowledge of mission-critical HVAC systems, including Fan Coil Walls, MDR/MMR CRAHs, air- and water-cooled chiller systems, and liquid cooling systems.
• Review and interpret CFD reports to assess impacts on equipment performance and inform design decisions.
• Estimate equipment loads and work with team members to oversee detailed load calculations.
• Apply knowledge of IEEC and ASHRAE 90.1 and 90.4 efficiency requirements for equipment and systems.
• Apply knowledge of data-center redundancy requirements and how tier-specific requirements affect design.
• Support master planning, client interactions, site planning for future buildings, and estimates of utility impacts.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior