Thermal Manager- Liquid Cooling Engineer

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A career at Flex offers the opportunity to make a difference and invest in your growth in a respectful, inclusive, and collaborative environment. If you are excited about a role but don't meet every bullet point, we encourage you to apply and join us to create the extraordinary.

Job Summary





To support our extraordinary teams who build great products and contribute to our growth, we’re looking to add a Thermal Manger-Liquid Cooling Engineer located in Milpitas, CA.

Reporting to the Quality Director, the Thermal Manager- Liquid Cooling Engineer will be Leading the design, analysis, testing, and implementation of liquid cooling and thermal management solutions for AI servers, HPC platforms, and data center infrastructure. Responsible for ensuring system thermal performance, reliability, manufacturability, and energy efficiency through simulation, testing, and cross-functional collaboration.

What a typical day looks like:

• Design and develop liquid cooling systems, including cold plates, cooling loops, manifolds, pumps, heat exchangers, tubing, and Cooling Distribution Units (CDUs).
• Perform thermal modeling, heat transfer calculations, and CFD simulations to evaluate and optimize cooling performance.
• Define thermal requirements and cooling strategies for new product introductions (NPI), AI, HPC, and data center applications.
• Develop and execute thermal validation, characterization, reliability, and qualification testing.
• Analyze thermal performance, identify improvement opportunities, and resolve thermal-related issues through root cause analysis.
• Collaborate with mechanical, electrical, manufacturing, quality, suppliers, and customers to implement effective cooling solutions.
• Support supplier selection, component qualification, and manufacturing readiness activities.
• Prepare engineering specifications, test plans, technical reports, and design documentation.
• Ensure compliance with customer, regulatory, and industry requirements.

The experience we’re looking to add to our team:

• Typically requires a bachelor’s degree in mechanical, Thermal, Aerospace, Chemical Engineering, or related field.
• 5+ years of experience in thermal management, ability to manage others, liquid cooling of electronics, or heat transfer applications.
• 3+ years of previous leadership/ managerial experience.
• Expertise in thermodynamics, heat transfer, fluid mechanics, and electronics cooling.
• Proficiency with CFD tools (ANSYS Fluent, Icepak, FloTHERM, Star-CCM+).
• Experience with thermal testing, system validation, and root cause analysis.
• Knowledge of thermal and liquid cooling components and architectures for data center or high-power electronics applications.

What you'll receive for the great work you provide:

• Full range of medical, dental, and vision plans
• Life Insurance
• Short-term and Long-term Disability
• Matching 401(k) Contributions
• Vacation and Paid Sick Time
• Tuition Reimbursement




Application Deadline:

Applications for this job position will be accepted for at least five days following the job posting start date below and continuing until the end date below or until the position is filled. This posting may close sooner due to application volume.

Job Posting Start Date 11-02-2026 Job Posting End Date 12-31-2026



The base pay range for this position is provided below. The final base rate offered will be determined using job-related, non-discriminatory criteria, including but not limited to experience, qualifications, geographic location, education, external market data, and internal equity.

$144,600.00 USD - $198,800.00 USD Annual

Job Category

Design, Process & Technology Engineering

Is Sponsorship Available?

No

Flex is an Equal Opportunity Employer and employment selection decisions are based on merit, qualifications, and abilities. We do not discriminate based on: age, race, religion, color, sex, national origin, marital status, sexual orientation, gender identity, veteran status, disability, pregnancy status, or any other status protected by law. We're happy to provide reasonable accommodations to those with a disability for assistance in the application process. Please email [email protected] and we'll discuss your specific situation and next steps (NOTE: this email does not accept or consider resumes or applications. This is only for disability assistance. To be considered for a position at Flex, you must complete the application process first).