Senior Mechanical Engineer

Location & work modality: HQ Rubí (near Barcelona) / hybrid model (3 days per week at the office)

Start: ASAP

Type of Contract: Full Time / Permanent

About Submer

The best way to introduce you to Submer is undoubtedly through our values: Sustainable Unique Bold Making Sense Empathetic and Reliable. If these resonate with you were sure you will find your place here in no time.

At Submer we believe that our digital world can be more sustainable more efficient and more environmentally friendly. Submer is solving the biggest problems of datacenter supercomputer hyperscale and edge applications to make that future possible.

Our multinational talented team has a huge passion in reducing IT environmental footprint and expertise in datacenter design and day-to-day operations. Were scaling our team and operations worldwide to meet growing international demand.

What impact you will have

We are seeking a Senior Mechanical Engineer to lead the design and delivery of critical mechanical systems for high-density data centers including both conventional air-cooled facilities and direct liquid cooling (DLC) environments. This role ensures the safe efficient and resilient operation of cooling and mechanical infrastructure . from chillers to fan wall CRAC/CRAH units CDU loops and rack-level liquid cooling; enabling next-generation compute platforms and mission-critical operations. The ideal candidate brings a proven track record in mechanical design for data centers and thrives in collaborative fast-paced multidisciplinary projects.

What youll do

Mechanical System Design & Engineering

• Develop detailed designs for mechanical and cooling systems (chillers cooling towers CRAC/CRAH units pumps piping valves CDUs FW RDHx and DLC loops).

• Define control strategies for primary and secondary cooling loops supporting both air and DLC environments.

• Produce design documentation including schematics layouts hydraulic diagrams specifications and equipment schedules.

• Evaluate and select equipment suppliers ensuring compliance with project performance requirements and client standards.

Thermal Performance & Analysis

• Perform load calculations hydraulic modeling and energy efficiency analysis.

• Optimize chilled water glycol and DLC systems to meet PUE and WUE targets.

• Assess redundancy schemes (N N1 2N) and their impact on system performance and resilience.

• Integrate mechanical design with electrical and IT infrastructure ensuring alignment across disciplines.

Commissioning & Delivery

• Support procurement processes technical reviews and submittal evaluations.

• Oversee factory acceptance tests (FATs) site acceptance tests (SATs) commissioning and system validation.

• Lead troubleshooting and root cause analysis for thermal or mechanical issues implementing corrective actions.

Compliance & Documentation

• Ensure designs comply with international standards local building codes ASHRAE and Uptime Institute best practices.

• Develop and maintain documentation including test protocols O&M manuals and method statements.

• Contribute to risk assessments and ensure safety compliance for fluid handling systems.

Collaboration & Expertise

• Partner with clients architects electrical engineers and IT teams to deliver integrated solutions.

• Provide subject matter expertise on high-density and DLC cooling strategies.

• Mentor junior engineers and contribute to knowledge sharing within the organization.

What youll need

• Bachelors or Masters degree in Mechanical Engineering (or related field).

• Minimum 7 years of experience in mission-critical mechanical design with demonstrable data center project delivery.

• Strong knowledge of HVAC chilled water and liquid cooling systems (DLC CDU RDHx etc.).

• Proficiency in mechanical design and analysis tools (e.g. Revit AutoCAD MEP HAP Pipe-Flo CFD).

• Familiarity with Tier certification requirements ASHRAE guidelines and international standards.

• Proven analytical problem-solving and troubleshooting skills.

• Strong communication and collaboration skills in cross-disciplinary teams.

• Ability to manage complex projects under tight deadlines in client-facing environments.

What we offer

• Attractive compensation package reflecting your expertise and experience.

• Restaurant Pass.

• Private Health Insurance.

• Languages classes (English).

• A healthy work environment with fresh fruits to energise and an on-site gym for active breaks.

• A great work environment characterised by friendliness international diversity flexibility and a hybrid-friendly approach.

• Youll be part of a fast-growing scale-up with a mission to make a positive impact offering an exciting career evolution.

Our Inclusive Responsibility
Submer is committed to creating a diverse and inclusive environment and is proud to be an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race color religion gender gender identity or expression sexual orientation national origin genetics disability age veteran status or any other protected category under applicable law.