Senior Mechanical Engineer

ABOUT YOU

Do you have an entrepreneurial spirit and a passion for engineering? Do you love designing and implementing complex electrical systems? Are you looking for a company that is constantly trying to push the boundaries of what it means to offer a better construction solution process by using design/build? If the answer is, “Yes!” then we have an opportunity that will excite you.

Who are we? We are ARCO, a Family of Construction Companies.

ARCO/Murray Engineering is seeking a Senior Mechanical Engineer to join our Mission Critical Engineering team in Downers Grove, Illinois. In this role, you will lead the full mechanical scope for hyperscale, colocation, and enterprise data center projects, guiding the development of complex cooling and mechanical infrastructure systems essential to high-availability facilities.

You will join an established but rapidly growing design/build group focused on delivering reliable, scalable, and efficient data center solutions. Our team collaborates closely with internal construction partners, project managers, and commissioning teams—working together to deliver world-class mission-critical environments.

• Industry-leading performance-based bonus program
• Employee Stock Ownership Plan (ESOP)
• Traditional and Roth 401k
• Tuition reimbursement for associates
• Scholarship for associates’ children up to $28,000 per child
• 1-month paid sabbatical after every five years of employment, plus $5,000 for travel
• 1-week paid volunteer leave each year
• 100% charitable match
• Medical, dental, and vision insurance coverage
• Paid parental leave

Typical base compensation for the Senior Mechanical Engineer role is between $90,000 and $130,000. Candidates with extensive experience may exceed this range. In addition to base salary, the role is eligible to receive discretionary bonus compensation based on individual and company performance.

• Lead the mechanical design process for mission-critical data centers, including chilled water systems, DX systems, CRAH/CRAC, heat rejection, and white-space cooling.
• Guide system development from early concept and basis-of-design through construction documentation, commissioning, and turnover.
• Apply ASHRAE TC 9.9 guidance and critical environment standards to ensure reliability and efficiency.
• Perform cooling load calculations, CFD coordination, and mechanical equipment sizing.
• Coordinate with electrical, controls, and architectural teams to ensure system integration supporting N, N+1, and 2N redundancy.
• Generate design and construction documents using Revit and AutoCAD.
• Support construction by reviewing RFIs, submittals, and field conditions.

• 7–20 years of mechanical engineering experience with data centers or mission-critical systems
• Bachelor’s degree in Mechanical Engineering, Architectural Engineering, or related field
• Proficiency with Revit and AutoCAD
• Strong understanding of critical cooling systems and redundancy strategies
• Ability to manage multiple fast-paced projects
• Experience in design/build is a plus
• Willingness to travel to project sites as required (e.g., 10-30%).
• Familiarity with engineering deliverables in a GC setting (i.e., design-build or EPC support) is a plus.

EOE, including disability/vets