Mechanical Commissioning Engineer

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.

The Mechanical Commissioning Engineer is a critical role responsible for assisting the mechanical validation program for large-scale, mission-critical data center construction projects. This role leads the QA/QC process across Levels 2 through 3 (L2–L3) and assists the end-to-end commissioning process across Level 4 through 5 (L4-L5) .

The successful candidate will provide technical oversight to 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.

L2–L3 Inspection: Lead Level 2 documentation verification, on-site installation and construction-readiness checks and Level 3 equipment startup and vendor startup validation.

L4 Functional Testing: Assist Level 4 functional performance testing, executing strict sequence-of-operations validation on complex mechanical systems.

L5 Integrated Systems Testing (IST): Assist the execution of L5 pull-the-plug heat-load testing to validate system redundancy, interlocks, failovers, and transient behaviors.

Scripts & Procedures: Review site-specific, rigorous test scripts, Method Statements (MOPs), and pre-functional checklists.

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.

The MCx Engineer must possess 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.

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

Experience: Minimum 1+ years of direct mechanical commissioning, engineering, or mission-critical facilities construction experience.

Data Center Focus: Experience leading L2–L3 programs on hyperscale, colocation, or enterprise builds.