Mesa Associates is seeking a Senior Mechanical Engineer to serve as a true generalist across our Mechanical Engineering department, delivering projects for our Generation, Industrial, and Government clients. This is a hands-on technical role: you will personally design HVAC systems, plant utilities, and piping scopes as project needs shift, without being boxed into a single specialty. You'll serve as a go-to resource who advises and mentors mid-career and junior staff across whatever scope you're supporting. We're looking for someone versatile, approachable, and just as comfortable picking up a new type of scope as sticking with a familiar one. Technical Expertise: HVAC, Utility Systems & Piping What We're Looking For • Expert, hands-on knowledge of industrial HVAC design, including heating, ventilation, air conditioning, exhaust, and specialized environmental control for equipment rooms, control rooms, switchgear rooms, and process spaces • Demonstrated ability to perform heating and cooling load calculations, size ductwork and equipment, and select chillers, air handling units (AHUs), fans, and dampers • Strong working knowledge of ASHRAE standards, the International Mechanical Code (IMC), and related codes as applied to industrial and power generation facilities • Hands-on knowledge of mechanical design codes including ASME, ANSI, API, and NFPA, with a strong understanding of ASME B31.1/B31.3 piping codes and ASME Boiler & Pressure Vessel Code Section VIII, API 650, and API 620 • Experience performing detailed stress analysis of piping systems, custom piping components, or fabrication assemblies using AutoPIPE and/or CAESAR II • Proficient with Plant3D, AutoCAD, MicroStation, and SolidWorks across HVAC, utility, and piping layouts, routing, and equipment coordination • Strong knowledge of power generation types, including coal, gas, and hydro, and how HVAC, utility, and piping systems support each • Working knowledge of utility systems, the supporting infrastructure that keeps plant equipment running (as distinct from HVAC or main process equipment), including: • Compressed air systems: supply instrument air and service air for pneumatic tools, instrumentation, and control valves • Cooling water systems: raw and closed-loop cooling water and cooling towers that remove heat from process equipment, condensers, and bearings • Potable water systems: provide clean water supply for facility and personnel use • Hydraulic systems: deliver pressurized fluid power for valve actuators, cranes, and similar equipment • Lubricating systems: supply oil or lubricant to pumps, turbines, compressors, and other rotating equipment to reduce wear What You'll Do • Personally perform HVAC load calculations, equipment selection, and ductwork design for assigned projects, from concept through issued-for-construction • Support the design of utility systems as needed, including compressed air, cooling water, cooling towers, potable water, hydraulic, and lubricating systems • Support piping design tasks as needed, including layout, routing, and basic sizing, working alongside engineers working on Piping & Pressure Systems • Perform process calculations, such as flow rate and pressure drop, directly within the Mechanical Engineering group; Mesa does not have a separate Process Engineering function, so this work sits with Mechanical • Perform walkdowns and collect detailed field data across HVAC, utility, and piping equipment to support scoping • Move fluidly between HVAC, utility, and piping assignments based on department and project needs Leadership & Team Role • Own deliverables directly across HVAC, utility, and piping-support work, in addition to reviewing and advising on the work of others • Work alongside junior and mid-career engineers, offering input, coaching, and mentorship across whichever scope you're supporting • Coordinate directly with other disciplines, including civil/structural, electrical, and controls, on integration-heavy scopes • Support proposal development and client-facing technical discussions across HVAC, utility, and piping scopes • Bring an open-door, team-oriented, versatile attitude that makes it easy for department engineers to ask questions, regardless of the topic Qualifications • Bachelor's degree in Mechanical Engineering and PE License (required) • 10+ years of experience with genuine breadth across HVAC, utility systems, and piping design, ideally in power generation, industrial, or facilities environments • Demonstrated, current hands-on design and calculation experience across multiple mechanical disciplines, not solely project oversight • Comfortable moving between different types of mechanical scopes as project needs shift, without needing to specialize in just one • A track record of coaching and developing engineering staff • Strong written and verbal communication skills with internal and external clients • Well organized, curious, and quick to spot issues and offer practical solutions • A collaborative, team-first mindset and a genuine willingness to roll up your sleeves and help wherever needed What You'll Earn • Paid Time Off • Holiday Pay - 10 Days Annually • Group Medical/Dental Insurance • Life Insurance (Company Paid) • Disability Insurance (Company Paid) • 401(K) Retirement Savings plan • 401(K) Matching Contribution • Section 125/Cafeteria Plan • Long Term Care Insurance • Tuition Reimbursement • Fitness Center Reimbursement • Annual Performance Bonus • 9/80 Work Schedule Option • FSA and HSA Options Notice to External Search Firms: Mesa Associates, Inc. and its subsidiaries do not accept unsolicited resumes and will not be obligated to pay a placement fee for unsolicited resumes. Mesa Associates, Inc. Talent Acquisition engages with approved search firms directly for specific hiring needs.