JOB TITLESenior Facility Engineer - MechanicalDEPARTMENTEngineering - Facility ReliabilityLOCATIONMontreal, QCWORK ARRANGEMENTHybridTRAVEL REQUIREMENTSSALARY RANGERole Summary5C is a full-stack AI digital infrastructure provider that designs, develops, and operates scalable AI factories and purpose-built data center campuses engineered for speed, density, reliability, sustainability, and long-term performance across North America.
As 5C's data center facilities transition from development into live operation, this role provides deep mechanical and cooling engineering authority for the operating portfolio. The Senior Facility Engineer - Mechanical is a senior technical anchor who owns the hardest live-site cooling and mechanical problems - from chilled water and air systems through liquid cooling for AI density - while mentoring engineers and setting the mechanical engineering bar for the function.
What You Will Do - Act as the primary mechanical engineering technical authority for operational facilities, providing expertise in chilled water systems, air handling systems, pumping systems, CRAH/CRAC units, heat rejection systems, and liquid cooling solutions designed for high-density AI environments.
- Lead root cause analyses, failure mode studies, and reliability assessments related to mechanical and cooling systems. Ensure the implementation, monitoring, and closure of corrective and preventive actions to maintain facility performance and resilience.
- Review and approve operational procedures (MOPs, SOPs, and EOPs) as well as high-risk interventions involving cooling systems, evaluating their impact on redundancy, capacity, and facility condition. Provide senior technical expertise during critical incidents, abnormal operating conditions, and major alarms, while participating in the L3/L4 technical escalation rotation.
- Represent the engineering team during design reviews, commissioning activities, Integrated Systems Testing (IST), and operational handovers. Identify single points of failure, redundancy losses, and thermal or capacity constraints; maintain technical documentation and control sequences; mentor engineers; and establish regional mechanical engineering technical standards.
What You Bring - Bachelor's degree in Mechanical Engineering or a closely related engineering discipline.
- 6+ years in data centers, critical facilities, or mission-critical mechanical/cooling infrastructure.
- Strong command of chilled water and air systems, pumps, heat rejection, and data center cooling design.
- Ability to read and interpret mechanical drawings, control sequences, commissioning reports, and test data.
- Strong judgment, written communication, and the ability to remain calm and direct under pressure during live events.
