Open roles
We hire only exceptional engineers: one to four founding leads, across four roles.
We are looking for A-players: engineers whose work stands out, with products shipped, solvers and models others rely on, and publications others build on. Each role reports to the founder, is full time, and requires a PhD in engineering or a closely related field. Salary ranges are base pay; the final offer depends on experience. Equity is granted as stock options with standard vesting. ★ Unlike any startup today, the early team may convert those options into common stock once we deliver the hardware defined in our contract at commercial readiness level, under the terms of our equity plan.
Lead Thermal Modeling Engineer
Grand Rapids, MI · hybridFull timePhD required
$140,000 – $175,000+ early equity
Own the physics of the AReCoS heat pump: the first-principles models of the refrigerant cycle, the water-cooled condenser and the water and ground loops that the product, its controller and its certification are built on.
What you will do
- Lead dynamic and steady-state modeling of vapor-compression cycles: moving-boundary and finite-volume heat exchangers, compressors, valves and two-phase flow.
- Model frost, heat and mass transfer and the water-cooled condenser, and turn the models into design decisions on capacity, efficiency and cold-weather performance.
- Build the model-based verification that proves each controller against the full physics model across the operating envelope.
- Plan and correlate laboratory and field tests with manufacturers and the national laboratory; predict AHRI ratings and cold-climate performance before hardware exists.
- Set modeling standards, reviews and documentation, and hire the thermal team.
What you bring
- PhD in mechanical, chemical or aerospace engineering, or a related field, with a dissertation in thermal-fluid systems, heat transfer or refrigeration.
- 10+ years of research or industry experience modeling vapor-compression, heat pump or HVAC&R systems.
- Expert command of MATLAB/Simulink, Modelica or Python, and refrigerant property tools such as CoolProp or REFPROP.
- A record of peer-reviewed publications or models that shipped in a product.
- Nice to have: frost and defrost physics, ground-source systems, model-based control design.
Apply for this roleSend your CV, a list of publications and a short note on the hardest model you have built.
Lead Mechanical Design Engineer
Grand Rapids, MI · on siteFull timePhD required
$135,000 – $170,000+ early equity
Own the design of the all-season heat pump rooftop unit, from the water-cooled condenser and refrigerant circuit to the cabinet, and carry it through prototypes, safety listing and the first production builds.
What you will do
- Lead the mechanical architecture of the 10-ton rooftop unit and the 5-ton residential heat pump: heat exchangers, piping, cabinet, airflow and serviceability.
- Design the patent-pending water-cooled condenser for performance, manufacturability and cost, using CFD and structural analysis where they matter.
- Own CAD, drawings, GD&T, tolerance stacks and the bill of materials, and run design reviews and DFMEA.
- Design for UL 60335-2-40, A2L refrigerant safety (R-454B), AHRI rating tests and ASHRAE 15 from the first sketch.
- Build and test prototypes with suppliers and manufacturing partners, and hire the mechanical team.
What you bring
- PhD in mechanical or aerospace engineering, or a related field, with research in thermal systems, heat exchangers or mechanical design.
- 10+ years designing HVAC&R, heat pump, automotive thermal or comparable electromechanical products taken to production.
- Expert command of SolidWorks, Creo or NX, with CFD or FEA experience.
- Working knowledge of refrigerant circuit design, brazed joints, pressure-vessel and safety standards.
- Nice to have: A2L refrigerant products, microchannel or plate heat exchangers, sheet-metal cabinets.
Apply for this roleSend your CV and two or three products or prototypes you designed, with your part in each.
Lead Manufacturing Engineer
Grand Rapids, MI · on site, with travelFull timePhD required
$130,000 – $165,000+ early equity
Take the AReCoS heat pump from prototype to production with established manufacturing partners: processes, quality, suppliers and cost, so the first commercial units ship in 2027 and every one after them is built right.
What you will do
- Select and qualify contract manufacturers and key suppliers for compressors, heat exchangers, controls and cabinets.
- Develop the production processes for the water-cooled condenser and the refrigerant circuit: brazing, leak testing, evacuation, charging and end-of-line run testing.
- Lead PFMEA, control plans, PPAP-style part approval and first-article inspection with partners.
- Own manufacturing cost, capacity and ramp plans for the first units and the scale-up after them.
- Prepare production for safety listing and rating-program audits, and hire the manufacturing and quality team.
What you bring
- PhD in manufacturing, mechanical, industrial or materials engineering, or a related field.
- 10+ years in manufacturing engineering for HVAC&R, appliance, automotive or comparable products, including a new product launch.
- Hands-on knowledge of brazing, heat-exchanger production, refrigerant handling and leak testing.
- Lean and Six Sigma methods; a Black Belt is a plus.
- Nice to have: contract-manufacturing launches, A2L refrigerant production lines, UL and AHRI audits.
Apply for this roleSend your CV and a short note on a product launch you led, and what you would do differently.
Lead CFD Engineer
Grand Rapids, MI · hybrid or remoteFull timePhD required
$140,000 – $175,000+ early equity
Own the flow and heat-transfer simulation behind the AReCoS heat pump: airflow through the rooftop unit and its coils, the water-cooled condenser, and the fans and cabinet, from high-fidelity studies to the fast, validated tools the design team uses every day.
What you will do
- Lead CFD of heat exchangers, fans, cabinets and airflow paths, including conjugate heat transfer, turbulence and two-phase or multiphase flow where it matters.
- Build and automate simulation workflows in OpenFOAM and commercial tools such as ANSYS Fluent: geometry clean-up, meshing, solver set-up, post-processing and parametric sweeps.
- Write and extend solvers, boundary conditions and utilities in C++ and Python, and run them in parallel with MPI on workstations and cloud clusters.
- Turn CFD results into reduced-order correlations for the thermal models and the controller, and validate them against laboratory and manufacturer test data.
- Set simulation standards, verification and mesh-convergence practice, and hire the CFD team.
What you bring
- PhD in aerospace, mechanical or chemical engineering, or a related field, with a dissertation in CFD, turbulence (RANS, LES or DNS) or numerical methods.
- 10+ years of research and industry experience in CFD, including solver development or advanced use of OpenFOAM, ANSYS Fluent or comparable codes.
- Strong programming in C/C++ and Python, with MPI or OpenMP, git and Linux.
- Meshing and post-processing tools such as Pointwise, ICEM, Gmsh, ParaView or Tecplot, and CAD such as SolidWorks.
- A record of peer-reviewed publications; nice to have: heat exchanger or HVAC&R flows, fan and aeroacoustic noise, GPU or high-order methods.
Apply for this roleSend your CV, a list of publications and a short note on a solver or simulation you built and how you validated it.
AReCoS is an equal opportunity employer. We welcome applicants of every background and consider all qualified applicants without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, veteran status or any other protected characteristic.