Lead Mechanical Commissioning Engineer

About Overwatch Mission Critical Overwatch is a service-disabled Veteran-owned small business (SDVOB) certified through the National Veterans Business Development Council (NVBDC) , offering construction professional services, talent acquisition, and general contractor support for the mission-critical infrastructure industry. Our mission is the construction and management of state-of-the-art data centers with the precision and reliability this industry demands. From high-end engineers to seasoned professionals, we deploy the people you need to get your data center off the ground. At Overwatch, it's more than a job. Its purpose. Position Overview The Lead Mechanical Commissioning Engineer is a critical leadership role responsible for directing the mechanical validation program for large-scale, mission-critical data center construction projects. This role manages the end-to-end commissioning process across Levels 1 through 5 (L1–L5). The successful candidate will provide ultimate technical oversight to Mechanical Cx Engineers, field technicians, and trade contractors. They will bridge the gap between design requirements and real-world field conditions, ensuring that hyper-complex HVAC, cooling, and automation systems deliver flawless, non-negotiable uptime under realistic failure scenarios.

Key Responsibilities

Phase Leadership & Execution (L1–L5)

Full Lifecycle Management:

Direct the commissioning sequence from initial factory acceptance testing (FAT/L1) to final Integrated Systems Testing (IST/L5) and ultimate turnover to Operations.

L2–L3 Inspection:

Oversee Level 2 documentation verification, on-site installation and construction-readiness checks and Level 3 equipment startup and vendor startup validation.

L4 Functional Testing:

Lead Level 4 functional performance testing, executing strict sequence-of-operations validation on complex mechanical systems.

L5 Integrated Systems Testing (IST):

Design, coordinate, and command the execution of L5 pull-the-plug heat-load testing to validate system redundancy, interlocks, failovers, and transient behaviors. Technical Quality & Commissionability

Document Review:

Critique complex mechanical design packages, P&IDs, sequence of operations (SOO) narratives, control scripts, and engineering submittals for risk and commissionability.

Scripts & Procedures:

Author and approve site-specific, rigorous test scripts, Method Statements (MOPs), and pre-functional checklists.

Complex Troubleshooting:

Root-cause analyze complex mechanical failures and controls errors discovered during high-stress testing environments.

Deficiency Tracking:

Contribute to the project issue log, ensuring mechanical discrepancies are categorized by risk, tracked, and remediated by appropriate vendors without impacting the master schedule. Team Management & Stakeholder Alignment

Field Direction:

Manage and prioritize work assignments for a team of internal field commissioning engineers and third-party technicians.

Interface Point:

Serve as the unified mechanical voice and primary point of contact connecting the client, general contractors, mechanical/MEP sub-contractors, equipment vendors, and controls engineers.

Meeting Leadership:

Represent the mechanical commissioning discipline in master schedule reviews, construction coordination meetings, and client-facing performance updates. Technical Domain Expertise The Lead Engineer must possess deep hands-on expertise validating the installation, tuning, and failure modes of the following critical systems:

Chilled Water Systems:

Centrifugal/air-cooled chillers, cooling towers, primary/secondary pumping loops, and thermal energy storage.

Air Handling Systems:

Computer Room Air Handlers (CRAHs), Computer Room Air Conditioners (CRACs), Direct/Indirect Evaporative Cooling (DEC/IEC) systems, and Fan Wall Arrays.

Advanced Liquid Cooling:

Direct-to-Chip (DLC) cooling manifolds, Coolant Distribution Units (CDUs), and immersion cooling infrastructure.

Controls & Automation:

Building Automation Systems (BAS), Direct Digital Controls (DDC), and Programmable Logic Controllers (PLCs) monitoring environmental setpoints.

Support Infrastructure:

Fuel oil storage/transfer systems, fire suppression/pre-action loops, and plumbing systems. Job Qualifications Required

Education:

Bachelor’s degree in Mechanical Engineering, HVACR, Construction Management, or equivalent technical field experience.

Experience:

Minimum 3+ years of direct mechanical commissioning, engineering, or mission-critical facilities construction experience.

Data Center Focus:

Minimum 2+ years of dedicated data center project experience, with demonstrated experience leading L1–L5 programs on hyperscale, colocation, or enterprise builds. Physical & Travel Requirements This position is heavily tied to deployment sites. It may require traveling 50% to 65% of the time. Ability to navigate construction sites, climb ladders, and lift up to 30 lbs.

Benefits

Overwatch Construction offers a competitive salary and benefits package, including health insurance, dental insurance, vision insurance, life insurance, 401(k) retirement plan, paid time off, and relocation assistance available. OVERWATCH is committed to creating a diverse work environment and is proud to be an Equal Opportunity Employer. OVERWATCH considers candidates regardless of race, color, religion, sex, sexual orientation, gender identity, national origin, disability or veteran status.