Critical Systems Commissioning lead - Mechanical

Critical Systems Commissioning lead - Mechanical Silent-Aire - Dublin What you will do

We are seeking an experienced Mechanical Critical Systems Commissioning Lead to help develop and lead the commissioning strategy for advanced cooling systems supporting next-generation data centre applications. This is a technical role within our central commissioning function, combining hands-on commissioning expertise, technical leadership and development of commissioning standards. You will work across product development, factory testing and site deployment, supporting regional teams to ensure safe, repeatable and high-quality commissioning from design review through FAT, SAT, integrated systems testing (IST) and final handover. The role is particularly suited to an experienced mechanical commissioning professional with a strong background in hydronic systems, HVAC, chilled-water systems or mission-critical infrastructure who wants to develop further expertise in liquid-cooled data centre technology.

How you will do it

Commissioning Strategy & Technical Leadership Develop and own the mechanical commissioning strategy for liquid-cooled and mission-critical cooling products. Define commissioning philosophy, test levels, hold points, acceptance criteria and documentation requirements. Provide design-for-commissioning input during design reviews and new product development. Act as a senior technical resource for mechanical commissioning issues, troubleshooting and risk resolution. Drive lessons learned and continuous improvement into future product designs and commissioning processes.

Systems Scope

The role will cover a range of cooling and mechanical infrastructure, including:

• Direct-to-Chip (DTC) liquid cooling systems.
• Coolant Distribution Units (CDUs).
• CRAHs, AHUs and other mission-critical cooling equipment.
• Chilled-water and secondary heat-rejection systems.
• Chillers, dry coolers and plate heat exchangers.
• Pumps, valves, pipework, filtration and water-treatment systems.
• Rear Door Heat Exchangers (RDHx), where applicable.
• Leak detection and containment systems.
• Mechanical interfaces with BAS/BMS/PLC controls.
• Associated instrumentation, sensors and control valves.

Procedures & Documentation Development

Develop, review and maintain commissioning documentation including:

• Mechanical commissioning plans and procedures.
• Pre-commissioning, flushing, cleaning and water-quality procedures.
• Hydrostatic/pneumatic pressure and leak-testing procedures.
• Functional performance testing.
• Thermal performance and load-validation testing.
• Failure-mode and redundancy testing.
• FWT, FAT, SAT and integrated testing procedures.
• Clearly defined and measurable pass/fail criteria.

Factory, Site & Regional Team Support

Provide governance and technical oversight to factory and regional commissioning teams. Support and audit commissioning execution against agreed standards and procedures. Participate in and witness Factory Acceptance Tests (FAT), Site Acceptance Tests (SAT) and critical site activities. Support troubleshooting, root-cause analysis and system optimisation. Help develop regional commissioning capability through coaching, technical guidance and lessons learned.

Integrated Testing & Handover

Work closely with electrical, controls, engineering and project teams during:

• Integrated Systems Testing (IST).
• Failure-mode and redundancy testing.
• System load and thermal performance testing.
• Client demonstrations and acceptance testing.
• Final commissioning documentation and handover.
• Transition into live IT load and operational readiness.

What we look for

Experience & Qualifications Relevant mechanical commissioning, HVAC, building-services or mission-critical engineering experience. Strong practical knowledge of hydronic systems, chilled-water systems and mechanical cooling equipment. Experience commissioning data - centre or liquid-cooling systems is highly desirable but not essential where the candidate can demonstrate strong transferable commissioning experience. Working knowledge of: Hydronic system operation, balancing and commissioning. Pumps, valves, heat exchangers and associated pipework. Pressure testing, flushing and water-quality requirements. Controls and BMS/PLC interaction. Functional performance testing. Redundancy and failure-mode testing. Experience supporting FWT, SAT or site commissioning activities. Relevant mechanical/building-services engineering qualification, trade background or equivalent industry experience. Experience working across multiple locations or with regional teams is advantageous.

What will make you successful

You will be comfortable operating as both a technical authority and practical commissioning engineer. You should be able to challenge designs constructively, troubleshoot complex systems, produce clear technical documentation and make sound engineering decisions under pressure. You will also be comfortable travelling to support factory testing, first-of-kind deployments and critical commissioning activities as required.

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