Mechanical Engineer

Apex Systems; Greater London; On-site; GBP 45,000 - 65,000; Full time

Job summary

Apex Systems is seeking a mechanically biased Data Center Facility Engineer to support operation and maintenance of critical cooling and water infrastructure in a data centre environment.

The role collaborates with electrical and controls teams to own mechanical systems and fluid management across the facility, performing routine maintenance and troubleshooting with a strong focus on reliability and uptime.

Qualifications

• Experience with mechanical building services, HVAC, or critical cooling infrastructure.
• Ability to read and interpret technical drawings, schematics, and maintenance procedures.
• Knowledge of water hygiene, Legionella control, ACOP L8, and HSG274 guidance.

Responsibilities

• Operate, maintain, and troubleshoot mechanical cooling infrastructure including chillers, AHUs, FCUs, pumps, and related plant.
• Maintain chilled water and pressurised water systems, including pipework and valves.
• Carry out planned preventative maintenance and reactive repairs on mechanical assets.
• Perform pressure testing, leak detection, inspections, and fault diagnosis on cooling/water systems.
• Monitor system performance and identify efficiency improvements.
• Support commissioning and decommissioning during upgrades and capacity expansions.

Skills

Mechanical services

HVAC systems

Critical cooling

Chillers

AHUs

Pumps

Pipework

Reading drawings

Legionella control

Water hygiene

BMS/SCADA

Fluid distribution

Education

NVQ Level 3 in Mechanical/Building Services or related discipline

Tools

BMS/EPMS/SCADA monitoring systems

Job description

We are seeking a mechanically biased Data Center Facility Engineer to support the operation and maintenance of critical cooling and water infrastructure within a mission-critical data centre environment.

This hands-on role focuses on maintaining mechanical cooling systems, water distribution networks, and associated plant equipment to ensure maximum reliability, efficiency, and uptime. The successful candidate will work alongside electrical and controls teams while taking ownership of mechanical systems and fluid management across the facility.

Key Responsibilities

• Operate, maintain, and troubleshoot mechanical cooling infrastructure including chillers, cooling towers, AHUs, FCUs, pumps, heat exchangers, and associated plant.
• Maintain chilled water, condenser water, and other pressurised water systems, including pipework, valves, fittings, and distribution networks.
• Carry out planned preventative maintenance (PPM) and reactive repairs on mechanical assets.
• Perform pressure testing, leak detection, system inspections, and fault diagnosis on water and cooling systems.
• Support the operation and maintenance of coolant distribution units (CDUs) and liquid cooling infrastructure.
• Monitor cooling system performance and identify opportunities to improve efficiency, reliability, and thermal performance.
• Support commissioning and decommissioning activities during infrastructure upgrades and capacity expansions.
• Maintain water treatment programmes in accordance with industry standards and legislation, including temperature monitoring, water quality testing, chemical treatment, and Legionella control measures.
• Respond to mechanical alarms, cooling incidents, leaks, and equipment failures in line with operational procedures and service levels.
• Maintain accurate maintenance records, inspection reports, and system documentation.
• Work closely with controls and facilities teams to support BMS, EPMS, or SCADA monitoring systems.
• Ensure all work is completed safely and in accordance with permits, risk assessments, method statements, and site procedures.
• Support continuous improvement activities to increase system uptime and reduce downtime.

Required Skills & Experience

• Experience working with mechanical building services, HVAC systems, or critical cooling infrastructure.
• Strong knowledge of chillers, AHUs, cooling systems, pumps, pipework, and associated mechanical plant.
• Experience carrying out planned and reactive maintenance within a critical facilities, industrial, manufacturing, healthcare, utilities, or data centre environment.
• Ability to read and interpret technical drawings, schematics, and maintenance procedures.
• Experience working with pressurised water systems and fluid distribution networks.
• Knowledge of water hygiene, Legionella control, ACOP L8, and HSG274 guidance.
• Understanding of fluid dynamics, pressure systems, heat transfer, and cooling system operation.

Qualifications

• NVQ Level 3 (or equivalent) in Mechanical Engineering, Electrical Engineering, Mechatronics, Building Services, HVAC, Plumbing & Heating, or a related discipline.

Preferred Experience

• Data centre or critical facilities experience.
• BMS, EPMS, or SCADA monitoring systems.
• Cooling towers, water treatment programmes, or closed-loop cooling systems.
• Liquid cooling technologies including CDUs and direct-to-chip cooling.
• IOSH Managing Safely, NEBOSH, or equivalent health and safety qualifications.
• Experience supporting commissioning and infrastructure projects.