Mechanical Engineer IV

Who We Are

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.

What Drives Success

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

What We Are Looking For

* 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 Wind Chill.

* Experience with UL/ETL, AHRI testing, and DOE regulatory requirements.

* Strong analytical, problem-solving, and communication skills.

* Demonstrated…