Senior Mechanical Engineer - Thermal & Air Systems

We are looking for a hands-on Senior Mechanical Engineer to join our Core Technology team, focused on the design and development of hot air handling systems for high-temperature energy storage applications. This role is central to delivering robust ducting networks, plenum assemblies, dampers, louvers, and associated air-distribution equipment that operate reliably at elevated temperatures. The ideal candidate combines analytical depth with design and assembly knowledge, and a passion for solving complex thermal-fluid engineering challenges.

What You’ll Do

Responsibilities include but are not limited to:

• Lead the mechanical design of hot air ducting systems, plenum assemblies, and air distribution components operating at temperatures up to 1000 °C.
• Design, specify, and validate dampers (isolation, control, backdraft, and diverter types) and louvers for high-temperature service, including actuator selection and leakage performance requirements.
• Design plenum assemblies, transition pieces, expansion joints, and support structures that accommodate thermal growth while maintaining structural integrity.
• Define subsystem requirements and develop verification and validation (V&V) plans aligned with system-level performance, safety, and operational goals.
• Prepare technical documentation—drawings, specifications, and engineering calculations—for internal teams, fabricators, and external stakeholders.
• Perform thermal and fluid analyses to identify key design drivers; use FEA where required to confirm mechanical performance under thermal and pressure loads.
• Lead and contribute to FMEA activities to identify and mitigate risk; develop and execute test strategies, including design of experiments (DOE), to validate system performance and reliability.
• Support prototyping, test plans, vendor qualification, and iterative development across high-temperature metallic and insulated duct assemblies.
• Lead the air circulation sub-system for product development of Rondo’s current and next generation product line. Follow Rondo product development phase gate process, lead Rondo product development reviews and maintainphase gate documentation.
• Develop top level system architecture for Rondo Heat Battery Air Management and Heat Delivery systems.
• Lead and participate in design reviews, schedule planning, and cross-functional progress reporting to drive program execution.
• Utilize CAD and PLM tools (SolidWorks preferred) for design, documentation, and configuration control of air-system components.
• Collaborate with manufacturing, construction, and supply chain teams to improve quality, establish process controls, and resolve root causes of field failures.
• Develop duct sizing, routing, and layout using first-principles pressure drop calculations and 1D flow network analysis, ensuring compliance with velocity, pressure, and thermal expansion requirements.
• Solve coupled multiphysics problems involving heat transfer (conduction, convection, radiation), fluid flow, and structural behavior in high-temperature air systems.

What You’ll Bring

• Bachelor’s or Master’s degree in Mechanical Engineering or a related discipline.

• 7+ years of engineering experience with a focus on air systems, industrial gas handling, or high-temperature process systems; energy industry experience preferred.

• Proven track record of taking designs from concept through fabrication and commissioning for one or multiple of following systems: Dampers, actuators, louvers, ducts, plenum, furnace

• Experience with high temperature equipment design. Experience with high-temperature materials: stainless steels, Inconel, refractory linings, ceramic fiber insulation, and high-temperature expansion joint materials.

• Knowledge of relevant codes and standards (e.g., API, ASME, NFPA, applicable EN standards for industrial ducting and pressure equipment).

• Strong cross-functional collaboration and communication skills; ability to work effectively with construction, commissioning, and operations teams.

• Demonstrated commitment to engineering rigor, quality documentation, and schedule execution.

• Track record of driving cost reduction through design optimization and standardization.

• Experience mentoring and developing junior engineers with authenticity and care. Bonus Points!

• Experience working in an industrial construction environment (site supervision, field engineering).

• Ability to perform CFD analysis on duct networks, plenums, and damper assemblies.

• Familiarity with refractory-lined or high temperature ceramic fiber ductwork design and installation practices.

• Experience integrating high-temperature blower or fan systems with duct networks.

• Background in damper-actuator design, heat recovery systems, waste heat utilization, thermal-mechanical systems or thermal energy storage applications. What We Offer:

• Comprehensive Medical Benefits

• Dental & Vision Benefits

• Life Insurance and ADD

• Up to 13 paid holidays per year, in addition to a company week-long holiday in December

• Flexible time off policy

• Catered lunches on-site

• 401(k) plan with company match

• Rondo HQ is close to Oakland airport - one block from the Bay - and has stunning Bay views! This role necessitates being on-site at our Alameda HQ several times per week. The estimated annual salary range for this role is $170,000 to $200,000 and it would be eligible for Rondo's excellent benefits listed above pl us additi o nal compe nsation in the form of equity. Please note that some pay bands may have wide ranges of compensation to accommodate candidates' diverse sets of skill levels and experience.

About the Company

We are transforming industrial decarbonization with our innovative Rondo Heat Battery technology. Rondo is deploying low-cost, zero-carbon Rondo Heat Batteries to accelerate the deployment of renewable energy and to significantly decarbonize industrial processes that are commonly thought of as "difficult-to-decarbonize". Our heat batteries charge from intermittent renewables to provide high temperature, continuous heat for customers safely, reliably, at an unprecedented 98% efficiency - and at a cost point that is lower than any other method.

Our technology is designed to replace fossil-fired boilers. By enabling industries to adopt renewable energy without costly factory changes, we are accelerating the transition to a sustainable future. With over $160 million in funding and partnerships across critical industrial sectors, Rondo is scaling rapidly to meet global demand.

Rondo Energy is an equal opportunity employer. We strive to create a supportive and inclusive workplace where contributions are valued and celebrated, and our employees thrive by being themselves and are inspired to do their best work. We seek applicants of all backgrounds and identities, across race, color, ethnicity, national origin or ancestry, citizenship, religion, sex, sexual orientation, gender identity or expression, veteran status, marital status, pregnancy or parental status, or disability. Applicants will not be discriminated against based on these or other protected categories or social identities.

Rondo is committed to the full inclusion of all applicants. If reasonable accommodation is needed to participate in the interview process, please let our recruiting team know .

We proactively work to design hiring processes that promote equity and inclusion while mitigating bias.

Note to Recruitment Agencies: Rondo does not accept unsolicited agency resumes. Furthermore, Rondo Energy does not pay placement fees for candidates submitted by any agency other than its approved partners.