Inside the AI Boom: The Cooling Layer — Who Keeps the GPUs From Melting and Who’s Hiring
- maktinta
- Jul 15
- 9 min read
Updated: 8 hours ago
Every watt that goes into an AI data center comes out as heat. A single modern rack can run as high as 250 kW; some Helios and GB300 configurations land near 200 kW. Air cooling collapses past about 50 kW per rack and is impossible past 100 kW. The parent piece — “The AI Gold Rush: Who’s Selling the Shovels” — flagged this as one of the most under-appreciated layers of the entire build-out. None of the chiller, dry-cooler, pump, or thermal-materials companies that bridge a chiller plant to a Blackwell die can build capacity fast enough. Modine alone commissioned four new chiller production lines in a single quarter and has four more on the way.
Five sub-layers: chillers + applied-thermal OEMs, direct-to-chip and CDU specialists, intelligent pumps + flow controls, dry coolers + heat-rejection, and thermal interface materials. Then careers at five companies hiring hardest.
1. Chillers + Applied-Thermal OEMs
Trane, Johnson Controls, Carrier, and Daikin are the big four building-thermal OEMs. All four have pivoted into AI data-center cooling — most explicitly.
Trane completed its acquisition of LiquidStack in March 2026 and earlier swallowed Stellar Energy; FY26 revenue was $4.97 billion (+6%), backlog hit a record $10.7 billion, Americas commercial HVAC bookings ran +40% YoY and Applied bookings +100%.
Johnson Controls launched a second AI Factory Reference Design Guide in May 2026, focused on air-cooled chiller architectures scalable to a 1 GW campus.
Carrier introduced high-ambient-temperature chillers purpose-built for AI workloads and is integrating recent acquisitions to enter the market in earnest.
Trane built its thermal-management reference design around NVIDIA’s Omniverse DSX blueprint — effectively embedding itself into the design standard for gigawatt AI factories.
Player | AI signal | Latest figure | Trajectory |
Trane Technologies | LiquidStack + Stellar acquisitions | $4.97B FY26 (+6%); $10.7B backlog | Commercial Applied bookings +100% YoY |
Johnson Controls | AI Factory Reference Design v2 | Air-cooled chillers for 1 GW scale | Acquisitions complementing chiller stack |
Carrier | High-ambient AI chillers introduced | Late entrant; ramping | 3–5 yr execution window to scale |
Daikin | Largest global HVAC OEM | Expanding U.S. chiller capacity | Aggressive AI chiller pipeline |
2. Direct-to-Chip + CDU Specialists
Once you’re past 50 kW per rack you stop trying to cool air and start cooling silicon directly. Cold plates sit on top of the GPU die; a coolant-distribution unit (CDU) at the rack or row level moves the warm fluid into the facility loop.
Vertiv (XDU), Motivair (now Schneider Electric), CoolIT (now KKR), and Asetek dominate. There is overlap with post #2 (server integration), because most of these CDUs are installed at the ODM stage, not in the field. Volume is being limited by cold-plate machining capacity and CDU pump availability, not demand.
Player | Role | Status | Trajectory |
Vertiv (XDU) | Rack and row-level CDUs | Part of $15B+ backlog | Expanding CDU capacity globally |
Motivair | CDUs + RDHx; Schneider $1.13B acq. | Schneider-scale distribution unlocked | Pre-integrated with EcoStruxure |
CoolIT Systems | Cold plates + CDUs (KKR-owned) | Volume cold-plate ramp | OEM-integrated supply |
Asetek | Direct-to-chip + ILC | Public; smaller scale | Repositioning toward AI rack market |
LiquidStack | Single-phase immersion | Now part of Trane | Reference designs around NVIDIA DSX |
3. Intelligent Pumps + Flow Control
A liquid-cooled hyperscale data center can have thousands of separate coolant loops, each modulating flow in real time to match GPU load. Grundfos and Xylem dominate intelligent pump systems for liquid-cooled facilities — variable-speed, IoT-enabled units integrated with DCIM platforms.
Wilo and Armstrong round out the field. The data-center cooling-pump market was sized at ~$2.5 billion in 2025 and is on track for $4 billion+ by 2033 (~8% CAGR). That math is conservative if liquid cooling continues to take share. Grundfos opened a new U.S. application engineering center in 2026 specifically for hyperscale DC accounts.
Player | Focus | AI signal | Trajectory |
Grundfos | Variable-speed intelligent pumps | U.S. AI DC application center (2026) | Largest single share globally |
Xylem | Pumps + smart water systems | Hyperscale DC deployment growing fast | Multiple long-term hyperscaler PSAs |
Wilo | European intelligent pumps | DC liquid-cooling pump growth | U.S. capacity expanding |
Armstrong | Design-envelope pumps + controls | Embedded DCIM integration | Canadian-led DC pump push |
Mkt size | Data-center cooling pumps | $2.5B (2025) → $4B+ (2033) | Conservative if LC keeps gaining |
4. Dry Coolers + Heat Rejection
Once you’ve moved heat off the chip and through the facility loop, you still have to reject it to the atmosphere. That last step is a dry cooler, an adiabatic cooler, or a cooling tower.
Modine, Baltimore Aircoil Company (BAC), EVAPCO, and SPX Cooling Tech are the relevant names. Modine is the most explicit AI play in the group: data-center sales rose 31% sequentially in fiscal Q3 2026 on >$400 million in quarterly revenue, and the company commissioned four new chiller production lines in a single quarter with four more on the way. None of these companies can build capacity fast enough.
Player | Focus | Latest figure | Trajectory |
Modine | Chillers + dry coolers for DC | Q3 FY26 DC rev >$400M (+31% q/q) | 4 new lines added; 4 more underway |
Baltimore Aircoil (BAC) | Cooling towers + dry coolers | Expanding hyperscale share | Long-term contracts w/ multiple hyperscalers |
EVAPCO | Cooling towers + adiabatic | Strong DC mix shift | Pre-fabricated AI campuses |
SPX Cooling Tech | Industrial cooling towers | Reshaped for DC volume | Capacity bound across all SKUs |
5. Thermal Interface Materials + Cold-Plate Manufacturing
The least-glamorous link in the chain: a 1 mm-thick layer of thermal grease, a phase-change material, or a metal-mesh pad that sits between the GPU package and the cold plate. Pick wrong, and the GPU thermal-throttles. Henkel (Bergquist), Honeywell, and Parker Hannifin (Chomerics) supply most of the high-performance TIMs. Specialty cold-plate machining — typically copper or copper-tungsten — is its own bottleneck, with most volume sitting at a handful of Taiwanese, Korean, and U.S. machine shops. Almost none of this is public.
Player | Focus | AI signal | Trajectory |
Henkel (Bergquist) | Bergquist TIM line | Standard on multiple AI accelerators | Capacity expansion announced |
Honeywell | Thermal interface materials | Liquid-metal TIM portfolio | DC mix shift growing |
Parker Hannifin (Chomerics) | Conductive TIMs | Multi-decade EMI/Thermal heritage | Pulled into AI accelerator BOMs |
Specialty cold-plate shops | Cu / Cu-W cold plates | Most private; capacity-bound | Volume limited by ODM integration |
Careers: Five Companies, Five Buckets, One Taxonomy
The five companies below — Trane Technologies, Johnson Controls, Vertiv, Modine, and Grundfos — cover most of the active hiring in the layer. Counts directional as of mid-June 2026.
Trane Technologies — record $10.7B backlog; HVAC + liquid-cooling hiring
Trane is hiring across the U.S. and globally, with a particularly strong technician-and-engineer pull in the southeastern U.S. (Tyler, TX; Pueblo, CO; La Crosse, WI) and a new liquid-cooling integration team in Pittsburgh following the LiquidStack acquisition. Average Trane hourly pay across the U.S. sits around $37.50. The recent careers portal launch (April 2026) consolidated all global postings into one site.
Bucket | Open reqs (approx.) | Typical entry-level requirements | Example titles |
Engineering | ~600 | BS ME/EE/ChemE; HVAC, controls, refrigeration, LC integration | Applied Engineer; Controls Engineer; LiquidStack Integration Engineer |
Operations & SC | ~250 | BS IE / Supply Chain | Manufacturing Engineer; Sourcing Manager — Components |
Finance & Accounting | ~80 | BS Finance / Accounting | FP&A Analyst — Americas Commercial; Cost Accountant |
Sales & BD | ~200 | BS technical or business | AE — Data Center; Solutions Engineer — Applied HVAC |
Corporate | ~60 | HR / Legal / IT | HR BP; Counsel — Commercial; IT Director |
Surprise: a Trane HVAC service technician with a community-college AAS pulls $27–$50/hour with strong overtime, and the data-center demand is making service-tech reqs one of the fastest-growing categories in the company.
Johnson Controls — air-cooled chillers and reference designs for 1 GW campuses
Johnson Controls’ AI Factory Reference Design Guide v2 made the company a deliberate participant in hyperscale standards-setting. The hiring mix reflects both an HVAC equipment business and a Tyco / Sensormatic security-and-controls portfolio. Milwaukee and Cork (Ireland) are the largest engineering centers; sales pull is heaviest in NoVA, Texas, and the Pacific Northwest where new hyperscale builds are concentrated.
Bucket | Open reqs (approx.) | Typical entry-level requirements | Example titles |
Engineering | ~500 | BS ME/EE; chillers, controls, fire/security | Chiller Engineer; Controls Engineer; Fire & Life-Safety Engineer |
Operations & SC | ~150 | BS IE / Supply Chain | Operations PM; Sourcing Manager |
Finance & Accounting | ~60 | BS Finance / Accounting | FP&A Analyst — Building Solutions NA; Revenue Accountant |
Sales & BD | ~200 | BS technical or business | AE — DC; Solutions Engineer — Applied HVAC |
Corporate | ~50 | HR / Legal / IT | HR BP; Counsel — Commercial; IT Director |
Surprise: JCI’s fire and life-safety business — Tyco — sells the same data-center customer who buys chillers. The cross-sell makes JCI’s solutions-engineering track unusually broad for a single hire.
Vertiv: thermal team specifically hiring fast
Vertiv’s thermal team — Liebert-branded — is hiring across Westerville, OH; Anderson, SC; and Mexico City. Critical-power and critical-cooling roles overlap inside the company, but on the cooling-specific side the demand is concentrated on CDU engineering, controls engineering, and DCIM software integration.
Bucket | Open reqs (approx.) | Typical entry-level requirements | Example titles |
Engineering | ~150 | BS ME / EE; thermal, controls, DCIM | Thermal Design Engineer; CDU Controls Engineer; Liebert Solutions Engineer |
Operations & SC | ~80 | BS IE / Supply Chain | Production Supervisor; Sourcing Manager — Thermal |
Finance & Accounting | ~30 | BS Finance / Accounting | FP&A Analyst — Thermal Segment |
Sales & BD | ~80 | BS technical or business | Solutions Engineer — Liquid Cooling |
Corporate | ~25 | HR / Legal / IT | HR Generalist |
Surprise: a Vertiv field-service tech with HVAC certification is now one of the most-recruited single profiles in the entire data-center cooling job market — short supply, high overtime, and growing customer base.
Modine — data-center revenue >$400M/qtr, +31% sequential; aggressive U.S. hiring
Modine is the most under-recognized direct AI cooling play in the layer. Headcount is concentrated in Racine, WI (HQ), Trenton, MO, and Lawrenceburg, KY, with new lines coming online in Mexico. The data-center segment is now growing inside a parent that historically served automotive HVAC and industrial — meaning a candidate with general HVAC, refrigeration, or industrial-controls experience can pivot cleanly into the DC segment.
Bucket | Open reqs (approx.) | Typical entry-level requirements | Example titles |
Engineering | ~120 | BS ME/EE; chillers, dry coolers, controls | Mechanical Design Engineer; Controls Engineer; Test Engineer |
Operations & SC | ~150 | HS to BS; manufacturing, planning, forklift | Production Supervisor; Materials Planner; Assembly Tech |
Finance & Accounting | ~25 | BS Finance / Accounting | FP&A Analyst — Climate Solutions; Cost Accountant |
Sales & BD | ~40 | BS technical or business | AE — Data Center; Solutions Engineer — Chillers |
Corporate | ~20 | HR / Legal / IT | HR Generalist; IT Site Manager |
Surprise: Modine is hiring assembly and test technicians in Trenton, MO at scale to staff the four newly-commissioned chiller lines. Local cost-of-living plus competitive industrial wages makes this one of the most underrated career-changer entries in the layer.
Grundfos — pumps for liquid-cooled DCs; new U.S. application center
Grundfos is hiring across U.S. and Denmark headquarters with a new application engineering center serving hyperscale DC accounts. Average U.S. hourly pay sits around $37, with most workers in the $31–$41 range. The bulk of openings sit in Brookshire, TX (largest U.S. plant); Olathe, KS; and the new applications team across multiple metros.
Bucket | Open reqs (approx.) | Typical entry-level requirements | Example titles |
Engineering | ~80 | BS ME / EE / ChemE; pumps, controls, DCIM integration | Application Engineer — Data Center; Controls Engineer; Mechanical Design Engineer |
Operations & SC | ~60 | HS to BS; manufacturing, planning | Production Operator; Materials Planner; Quality Engineer |
Finance & Accounting | ~15 | BS Finance / Accounting | FP&A Analyst — DC Segment |
Sales & BD | ~50 | BS technical or business | Solutions Engineer — DC Pumps |
Corporate | ~15 | HR / Legal / IT | HR Generalist; IT Service Lead |
Surprise: a single application engineer at Grundfos covering hyperscale DC accounts can influence ~$50–$100M in annual pump bookings. It is one of the highest-leverage non-quota engineering jobs in the cooling layer.
Where the Doors Are
For HVAC service technicians, Trane and Vertiv are running the most aggressive paid-overtime programs in the U.S. — community-college AAS in HVAC, refrigeration, or controls plus a willingness to travel opens doors at $30–$50/hour.
For assembly and test technicians without a four-year degree, Modine in Trenton, MO, and the Grundfos plant in Brookshire, TX, both run capacity expansions that should keep hiring at scale for at least the next 36 months.
For new mechanical-engineering grads, JCI’s Milwaukee and Trane’s La Crosse engineering centers are the largest single employers of applied-thermal engineers in the U.S.
For solutions engineers and sales engineers, Schneider Electric (cross-layer with post #4) plus the four big OEMs cover the broadest opportunity set.
For someone interested in a quieter, very high-leverage role: the data-center application-engineer track at Grundfos or Xylem is the kind of seat where one engineer can move $100M of bookings and never appear in a press release.
Good luck and stay tuned for the 3 more layers that goes into making a data center! In the mean time, check out other opportunities in part 1: chips and part 2: the server rack
Selected Sources
Trane Technologies FY26 results: $4.97B (+6%); $10.7B backlog (TIKR; Yahoo Finance)
Trane LiquidStack acquisition (March 2026, Facilities Dive)
Trane Stellar Energy acquisition (earlier; Trane IR)
Trane Omniverse DSX thermal reference design (parent piece)
Johnson Controls AI Factory Reference Design Guide v2 (May 2026)
Carrier high-ambient AI chillers introduced (parent piece)
Modine Q3 FY26 results: DC rev >$400M; +31% q/q (parent piece + Modine IR)
Modine 4 new chiller lines commissioned (parent piece)
Grundfos / Xylem intelligent pumps (parent piece)
Data-center cooling-pump market: $2.5B (2025) → $4B+ (2033) (parent piece)
Vertiv $15B+ backlog (parent piece + Vertiv IR)
Schneider Electric Motivair acquisition ($1.13B, 2024)
Trane careers — careers.tranetechnologies.com (re-launched April 2026)
Johnson Controls careers — johnsoncontrols.com/careers
Vertiv careers — vertiv.com/en-us/careers
Modine careers — modine.com/careers
Grundfos careers — jobs.grundfos.com; ZipRecruiter