Mechanical Project Manager - Data Centres (HVAC / Cooling) at Overwatch Mission Critical – London, England

Overwatch EMEA extends Overwatch Mission Critical’s proven delivery model across Europe, the Middle East, and Africa. We provide construction professional services, talent acquisition, and delivery leadership for mission-critical infrastructure projects, applying the same operational discipline, reliability, and veteran-led expertise that define our work in the United States.

From greenfield hyperscale development to complex retrofits and live-site expansions, our teams support the safe, efficient delivery of high-performance data centre environments. At Overwatch, it’s more than a job - it’s a purpose.

We are seeking an experienced Mechanical Project Manager with strong HVAC and data centre cooling expertise to support the delivery of mission-critical infrastructure across multiple European data centre construction projects.

you will oversee the delivery of mechanical and cooling infrastructure packages delivered by Tier 1 contractors and specialist mechanical subcontractors.

You will provide technical oversight, delivery governance, and risk management across mechanical systems including cooling plant, chilled water distribution, and white space cooling infrastructure.

This role requires strong understanding of data centre cooling architecture, mechanical construction sequencing, and commissioning readiness, ensuring contractor delivery aligns with project programme, quality standards, and operational requirements.

The role may involve engagement across multiple hyperscale or colocation data centre construction sites within Europe.

Provide oversight of mechanical and HVAC systems including:

• Chillers and central cooling plant

• Chilled water distribution systems

• CRAH / CRAC units

• Cooling towers

• Mechanical plant rooms

• Pump systems and heat rejection infrastructure

• BMS integration with cooling systems

Ensure contractor installation aligns with design intent, project standards, and operational requirements.

Oversee delivery of mechanical packages delivered by Tier 1 contractors and specialist mechanical subcontractors.

Responsibilities include:

• Reviewing contractor mechanical delivery plans

• Challenging sequencing and constructability risks

• Monitoring installation quality and compliance

• Ensuring mechanical milestones align with project schedule

• Escalating delivery risks to project leadership

Support programme governance across mechanical delivery phases.

• Monitor contractor progress against mechanical programme milestones

• Identify schedule risks linked to mechanical infrastructure delivery

• Review change requests impacting cooling systems or plant infrastructure

• Support mitigation strategies where delivery risk emerges

Support commissioning teams to ensure mechanical systems are delivered ready for testing.

Responsibilities include:

• Reviewing commissioning readiness of cooling infrastructure

• Supporting Level 3-5 commissioning activities where required

• Tracking defects and close-out of mechanical systems

• Supporting operational handover readiness

Support delivery across multiple European data centre projects.

Maintain consistent delivery standards through:

• Engagement with local project teams and contractors

• Structured reporting to programme leadership

• Coordination of lessons learned across projects

8+ years’ experience delivering mechanical or MEP infrastructure within large-scale construction projects.

Demonstrable experience with data centre cooling systems and mechanical plant infrastructure.

Strong understanding of:

• Data centre cooling architecture

• Mechanical plant installation and sequencing

• Chilled water systems and cooling distribution

• Mechanical commissioning and testing processes

• Construction delivery governance

Experience within hyperscale or colocation data centre construction environments preferred.

Experience operating in client-side or consultancy environments highly desirable.

Ability to support multi-site project delivery across Europe.