Critical Operations Supervisor - MECHANICAL (Australia)

Company Overview STACK Infrastructure builds, owns, and operates hyperscale and colocation data centers that power the world’s most ambitious technology companies. With a rapidly expanding footprint across APAC, STACK combines deep development expertise, flexible capital, and operational discipline to deliver critical digital infrastructure at scale. Our clients include the largest hyperscale cloud platforms. We are building a regional platform defined by speed of delivery, power reliability, and long-term partnership — and we are assembling the team to lead that effort. Summary/Objective The Critical Operations Supervisor

• Mechanical provides day-to-day operational leadership and technical governance to ensure the safe, compliant and reliable performance of all mechanical and cooling infrastructure across the site. This Monday-Friday role is accountable for coordinating mechanical operations, overseeing major works and maintaining regulatory and contractual compliance. The position participates in a rotating on-call roster to provide after-hours escalation, ensuring timely response to mechanical, thermal or cooling-related incidents. The Supervisor leads the Mechanical workstream across all shift teams, providing expert escalation on complex issues and coordinating critical activities such as planned shutdowns, cooling plant maintenance, thermal risk mitigation, troubleshooting and return-to-service (RTS) validation. This role is also responsible for ensuring mechanical training, competency and authorisation requirements are met. The Supervisor partners closely with site stakeholders to uplift procedures, enhance plant performance, strengthen operational readiness and continuously improve the mechanical reliability of the facility. This role directly supports STACK’s commitment to 100% uptime and a concierge-level customer service experience , ensuring risk is proactively managed, planned works are executed safely, and customer communications are clear, timely and professional. Essential Functions Reasonable accommodations may be made to enable individuals with disabilities to perform these essential functions. Critical Operations
• Uphold STACK’s 100% uptime objective by providing disciplined operational leadership and oversight of site mechanical and cooling systems.
• Ensure safe and compliant operation of all mechanical systems, including chilled water systems, CRAC/CRAH units, cooling towers, pumps, valves, filtration equipment and associated controls.
• Maintain real-time situational awareness of mechanical system condition, thermal stability, redundancy state and risk indicators through BMS/EPMS and field verification.
• Act as the primary mechanical escalation point for shift teams, providing real-time guidance, diagnostic support and risk evaluation.
• Lead the development, review and implementation of operational and maintenance procedures, including MOPs and SOPs for mechanical systems.
• Coordinate major mechanical activities, including planned shutdowns, incident response, corrective maintenance, onsite troubleshooting and programmed maintenance.
• Provide technical direction during planned maintenance, resets, cooling plant adjustments, valve alignments and energisations to ensure safe execution aligned to site procedures.
• Review and provide input into risk assessments, method statements, permit-to-work controls, isolations/LOTO and return-to-service documentation.
• Verify operational readiness following maintenance, resets, parameter changes or commissioning activities by confirming alarms, redundancy status, thermal performance and control sequences.
• Ensure all operational activities are carried out with due regard to health and safety, business risk and STACK’s 100% uptime objective.
• Act as incident manager for mechanical incidents when required, including during on-call periods.
• Coordinate vendor activities affecting mechanical systems, ensuring safe execution, alignment to site requirements and correct post-work configuration.
• Identify systemic risks, recurring thermal issues, capacity constraints and mechanical design limitations, and escalate as required.
• Improve operational documentation, including SOPs, MOPs, EOPs, shift logs, CMMS data quality, handover standards and alarm-handling procedures within the mechanical workstream. People
• Model outstanding safety behaviour, operational discipline and professional conduct.
• Provide coaching, uplift and technical mentoring to Senior Data Centre Specialists, Senior Critical Operations Technicians and Critical Operations Technicians to strengthen team capability and execution consistency.
• Reinforce high-quality shift communication, including clear escalation structures, accurate technical context and structured handovers.
• Ensure clear and accurate transfer of information between rotating shifts, maintaining continuity of operations and supporting consistent decision-making across the team.
• Support onboarding and technical familiarisation for new team members, clarifying operating boundaries, site safety and shift expectations.
• Collaborate effectively with Security, Projects, Operations and vendors to support safe and coordinated campus operations.
• Represent Critical Operations during customer visits, tours, audits and technical discussions, maintaining a concierge-level customer service approach at all times.
• Contribute practical insights and recommendations during toolbox talks, performance reviews, drills and operational meetings. Competencies
• Advanced operational judgement in a mission-critical environment.
• Strong technical capability in mechanical and cooling systems, including chilled water, HVAC and airflow management.
• Expert interpretation of plant telemetry, thermal behaviour, automation sequences and redundancy models.
• Structured troubleshooting and stabilisation capability under pressure.
• Proficiency with BMS/EPMS, CMMS and operational data platforms.
• Skilled in coaching, guiding and uplifting technical capability in others.
• Strong written and verbal communication suitable for incidents and customer interactions.
• Calm, authoritative presence during alarms, escalations and operational events.
• Strong coordination and oversight skills for work control, vendor interaction and RTS verification.
• Continuous improvement mindset focused on safety, reliability and operational excellence. Work Environment / Conditions
• This is a Monday-Friday position with rotating on-call requirements to support after-hours incidents and escalations.
• Work occurs across data halls, plant rooms, electrical/mechanical spaces and external plant areas; PPE is required under site policy.
• Participation in emergency response, readiness exercises and incident management activities is required. Travel Required
• Minimal travel expected; occasional travel between local STACK facilities may be required based on operational needs. Preferred Education and Experience
• Mechanical trade qualification, such as Certificate III/IV in Mechanical, HVAC or Refrigeration, or a mechanical engineering qualification with suitable Australian recognition or registration.
• Extensive experience in data centres or other mission-critical facilities, including utilities, hospitals, Defence or industrial environments.
• Demonstrated expertise operating and monitoring critical cooling and mechanical systems, including CRAC/CRAH, chilled water systems, pumps, cooling towers, airflow and filtration systems.
• Strong background in inspecting, triaging and stabilising mechanical plant under abnormal conditions.
• Experience reviewing MOPs, SOPs, EOPs, risk assessments and commissioning documentation.
• Ability to interpret mechanical schematics, chilled water diagrams, airflow layouts, control logic and OEM manuals.
• Knowledge of permit-to-work processes, isolations/LOTO and operational risk frameworks.
• Strong written and v