Commissioning Engineer

Hollybank Trustees Ltd; Denmark; On-site; DKK 700,000 - 1,000,000; Full time

Job summary

Hollybank Trustees Ltd. seeks an experienced Commissioning Engineer to deliver mechanical and electrical commissioning on a large-scale data centre project in Denmark.

You will work with the Client's Commissioning Authority (CxA) to ensure systems are fully documented, compliant, and handed over on time. Responsibilities include developing commissioning programmes, reviewing designs, preparing documentation, coordinating vendors, and leading inspections and testing across Level 1–5 processes.

Qualifications

• Degree or diploma in Mechanical, Electrical, or Building Services Engineering.
• Minimum 5 years commissioning experience on large onsite projects.
• Experience with MEP systems and integrated testing.
• Ability to interpret single-line diagrams, P&IDs, and specifications.

Responsibilities

• Develop and maintain the commissioning programme in line with the construction schedule, identifying system boundaries and energisation dates.
• Review design documentation and Employer's Requirements to confirm systems are commissionable and raise queries where not.
• Prepare and issue commissioning documentation for CxA and Client approval.
• Coordinate vendor specialists, subcontractors, temporary services, load banks, and test equipment ahead of each commissioning phase.
• Lead pre-functional inspection and static testing (Level 1–3) to verify installation quality and system integrity.
• Execute and witness functional performance testing (Level 4) and record results and defects.
• Support Integrated Systems Testing (Level 5), including black building tests and thermal load testing.
• Chair commissioning coordination meetings with Client, CxA, design team, and subcontractors.
• Manage system energisation with safe working practices, permits, lock-out/tag-out, and switching schedules.
• Track and close out commissioning issues and drive progress against milestones.
• Own the commissioning documentation set and ensure all test records and certificates are uploaded.
• Verify vendor start-up reports, calibration certificates, and warranty documentation are complete.

Skills

Excel

Technical writing

Coordination

Communication

P&ID reading

Education

Degree/diploma in Mechanical/Electrical/Building Services Engineering

Tools

Commissioning platforms

Job description

Location: On site / Denmark
job type: Permanent / Full-time
Sector and subsector: Engineering | General
Salary: Negotiable salary

To deliver the mechanical and electrical commissioning scope on a large-scale data centre project, taking systems from installation completion through pre-functional checks, functional performance testing, and integrated systems testing to client acceptance and handover. The Commissioning Engineer works alongside the Client's Commissioning Authority (CxA) and is accountable for ensuring Sensori's installed systems are demonstrably compliant, fully documented, and handed over on programme.

Responsibilities

• Develop and maintain the commissioning programme in line with the overall construction schedule, identifying system boundaries, dependencies, and critical energisation dates
• Review design documentation, specifications, and Employer's Requirements to confirm systems are commissionable as designed, and raise design queries where they are not
• Prepare and issue commissioning documentation — pre-functional checklists, functional performance test scripts, method statements, and system readiness checklists — for CxA and Client approval
• Coordinate the availability of vendor specialists, subcontractors, temporary services, load banks, and test equipment ahead of each commissioning phase
• Lead pre-functional inspection and static testing (Level 1–3), verifying installation quality, point-to-point checks, and system integrity before energisation
• Execute and witness functional performance testing (Level 4) on mechanical and electrical systems, recording results and defects in real time
• Support Integrated Systems Testing (Level 5), including black building tests, failure mode simulation, thermal load testing, and redundancy verification
• Chair and attend commissioning coordination meetings with the Client, CxA, design team, and subcontractors
• Manage system energisation in accordance with the project's safe systems of work, including permits, lock-out/tag-out, and switching schedules
• Track, categorise, and drive close-out of commissioning issues and punch items, escalating blockers that threaten programme milestones
• Own the commissioning documentation set, ensuring all completed test records, certificates, and results packages are uploaded and approved on the project Cx platform
• Verify vendor start-up reports, calibration certificates, and warranty documentation are complete and compliant
• Compile system turnover packages and support the O&M manual and as-built process ahead of final handover
• Coordinate client training and witness sessions on completed systems
• Produce weekly and monthly commissioning progress reports, including KPI and completion metrics for senior management
• Ensure all commissioning activity is planned and delivered in compliance with Sensori's EHS and quality management systems
• Verify that installation quality meets specification before systems are presented for testing, working closely with the QA/QC team
• Maintain full traceability of all test activity, results, and sign-offs

Requirements

• Degree, higher diploma, or trade apprenticeship in Mechanical, Electrical, or Building Services Engineering
• Minimum 5 years' commissioning experience in a large onsite environment, with demonstrable delivery on high-value projects (contract values in excess of €200m)
• Practical experience commissioning MEP systems across the full Level 1–5 process, including at least one project through to Integrated Systems Testing
• Working knowledge of critical infrastructure systems: generators, UPS, switchgear, LV/MV distribution, chillers, CRAH/CRAC units, pumps, CHW/LTHW distribution, BMS and EPMS
• Ability to read and interpret single line diagrams, P&IDs, schematics, and specifications
• Competent with commissioning management platforms and strong Excel skills for tracking and reporting
• Strong technical writing ability — test scripts, reports, and issue records to a client-presentable standard
• Ability to work both independently and as part of a multidisciplinary project team
• Excellent communication and organisational skills
• Excellent English language skills, written and spoken
• Willingness to work flexible hours, including nights and weekends, during peak testing periods
• Full clean driving licence and willingness to be site-based for the project duration