Mechanical Engineer IV

Lennox (NYSE: LII) Driven by 130 years of legacy, HVAC and refrigeration success, Lennox provides our residential and commercial customers with industry-leading climate-control solutions. At Lennox, we win as a team, aiming for excellence and delivering innovative, sustainable products and services. Our culture guides us and creates a workplace where all employees feel heard and welcomed. Lennox is a global community that values each team member’s contributions and offers a supportive environment for career development. Come, stay, and grow with us.

Innovate your career.

When you choose Lennox, you're getting the best.

When you work at Lennox, you’re among the best.

As a leading innovator of home and commercial, heating, cooling, refrigeration, air-quality, and related services, Lennox International is committed to helping our people innovate our products and their careers.

The Lead Engineer for Residential Air Handlers and Indoor Coils is responsible for the design, development, certification, and lifecycle management of residential HVAC air handling units and Evaporator Coil products. This role provides technical leadership across cross-functional teams, drives execution of product roadmaps, ensures regulatory and safety compliance, and delivers high-quality, cost-effective solutions that meet performance and reliability expectations.

DUTIES INCLUDE BUT ARE NOT LIMITED TO:

Product Development & Technical Leadership

• Lead end-to-end engineering for residential air handler and indoor coil platforms, including concept development, detailed design, prototyping, testing, and product launch.
• Own system- and component-level design decisions for sheet metal, plastics, heat exchangers, motors, blowers, insulation, controls integration, and refrigerant circuitry.
• Interpret test results and drive optimization recommendations for coil/air handler performance, refrigerant charge, airflow, and system configuration to meet regulatory and market efficiency targets.
• Develop, analyze, and validate system performance ratings (SEER2, EER2, HSPF2, capacity ratings, and AHRI matchups) through lab testing, data modeling, and cross-functional collaboration.
• Lead Air Handler electric heat testing and certification activities to ensure all electric heat modules and integrated air-handler assemblies meet UL 60335-2-40 safety requirements, including thermal protection, electrical clearances, wiring, component compliance, and abnormal operation testing.
• Drive engineering execution for new product introductions, value engineering initiatives, and sustaining engineering efforts.
• Guide junior engineers and provide peer review for design evaluations, calculations, DFMEAs, and test plans.

Certification & Compliance

• Ensure all products meet applicable regulatory and industry requirements, including UL/ETL, AHRI standards, DOE efficiency requirements, regional codes, and refrigerant transition regulations.
• Lead certification testing and documentation processes, including performance mapping, safety evaluations, and reliability validations.
• Maintain strong working relationships with certification agencies and internal compliance teams.
• Testing, Validation & Quality.
• Define system-level verification and validation plans, including airflow, capacity, sound, pressure drop, condensate management, and reliability testing.
• Collaborate with test labs to interpret data, troubleshoot issues, and optimize performance.
• Drive root-cause analysis and corrective actions for field issues, quality deviations, or manufacturing defects.

Cross-Functional Collaboration

• Partner with program management, manufacturing engineering, supply chain, quality, and product management to deliver on schedule, cost, and performance targets.
• Support manufacturing plants with design releases, engineering changes, tooling decisions, assembly process, PFMEA inputs, and build issues.
• Work closely with sourcing and suppliers to optimize cost, improve component performance, and ensure long-term reliability.

Project & Documentation Management

• Lead engineering activities in alignment with phase-gate and Independent Design Review processes, ensuring clear documentation, timely deliverables, and risk mitigation.
• Approve drawings, specifications, CAD models, and engineering change notices.
• Develop and maintain technical design standards, best practices, and engineering guidelines for air handlers and indoor coils.

#LI-onsite #LI-JM1

• Bachelor’s degree in Mechanical Engineering, Aerospace Engineering, or related technical field.
• 8+ years of experience in HVAC product development.
• Strong understanding of air handlers, indoor coils, refrigeration principles, and airflow systems.
• Proficiency with CAD and BOM release/updates through Change Notice management tools like WindChill.
• Experience with UL/ETL, AHRI testing, and DOE regulatory requirements.
• Strong analytical, problem-solving, and communication skills.
• Demonstrated leadership in technical teams or product development programs.

Compensation: This is a salaried exempt role. The starting salary range for this role and market is between $118,000 - $155,400 annually. Factors that may affect starting salary include geography/market and the skills, education, experience, and other qualifications of the successful candidate. This position is also eligible for the BroadBase Incentive (BBI) program with a target payout of 2%. Employees in this role are not eligible for overtime.

Location and Schedule: This position is located in Carrollton, TX and will be in the office Monday through Friday. 

Benefits: Subject to applicable eligibility requirements, the following benefits are offered for this role: tuition reimbursement; medical, dental, and vision insurance; prescription drug coverage; 401(k) retirement plan; short-term disability insurance; 8 weeks paid birthing leave; 2 weeks paid bonding leave; life and long-term disability insurance.

Paid Time Off: Depending on date of hire, and subject to applicable eligibility requirements, new employees in this role also receive up to: 12 days paid time off, 2 paid well-being days, 1 paid volunteer day, 9 to 11 paid company holidays depending on the year, and 3 floating holidays per year. 

Our Culture: At Lennox, our Core Values of Integrity, Respect & Excellence are ingrained in the fabric of the organization. They define our culture – which is about how we do business and how we treat others. Lennox is not just a workplace; we are a global community that values each team member’s contributions. As an equal opportunity employer, we are committed to recruit, develop, and retain talented individuals from a wide range of backgrounds, ensuring that everyone has the opportunity to succeed and contribute to our continued growth and success. At Lennox, you’ll take pride in our brands, knowing you are part of something special. Come, stay, and grow with us! 

Disclaimers: The compensation and benefits information is accurate as of the date of this posting. Lennox reserves the right to modify this information at any time, with or without notice, subject to applicable law.

We may use automated tools, including artificial intelligence, to support parts of our hiring process, such as application review and interview scheduling. These tools assist our teams but do not replace human decision-making. If you need an accommodation or have questions, please contact [email protected].