In this article, we will list the 5 Best Small-Cap Data Center Cooling Stocks to Buy. Please visit 10 Best Small-Cap Data Center Cooling Stocks to Buy if you’d like to see an extended list.
For this article, we screened for U.S.-traded stocks with market caps between $250 million and $2 billion that have explicit exposure to data center cooling, thermal management, or the infrastructure systems that support heat removal in high-density data centers. Since the public small-cap market has few pure-play data center cooling companies, the screen was expanded to include companies operating in clearly related parts of the value chain. We then ranked the stocks by the number of hedge funds holding a stake in them as of Q1 2026 and limited the final selection to companies with recent news or business developments.
5. Limbach Holdings, Inc. (NASDAQ:LMB)
Number of Hedge Funds: 21
Limbach Holdings, Inc. (NASDAQ:LMB) is one of the best small-cap data center cooling stocks to Buy. On June 18, Limbach highlighted modular construction solutions for data centers, positioning its prefabrication and MEPC platform around faster delivery of mission-critical infrastructure. The company said it supports owners with utility plants, mechanical skids, equipment modules, prefabricated piping systems, design-assist work, BIM coordination, virtual construction, constructability reviews, logistics planning, commissioning, startup, and Day 2 operations.
The cooling relevance is direct enough for a small-cap screen because Limbach’s data-center work includes HVAC, mechanical systems, plumbing, electrical infrastructure, and controls, all of which sit around heat removal and uptime. As AI facilities push higher rack density, modular mechanical systems and prefabricated piping can help reduce on-site complexity and speed deployment of cooling-support infrastructure. Limbach also says its approach helps data-center owners maintain uptime, increase density, and scale facilities more efficiently, giving the stock a services-level angle on thermal infrastructure.
Limbach Holdings, Inc. (NASDAQ:LMB) designs, installs, manages, services, and maintains HVAC, mechanical, electrical, plumbing, and control systems for mission-critical facilities, including data centers.
4. Ameresco, Inc. (NYSE:AMRC)
Number of Hedge Funds: 22
Ameresco, Inc. (NYSE:AMRC) is one of the best small-cap data center cooling stocks to Buy. On June 23, Ameresco announced two Advanced Metering Infrastructure contracts with Baytown and Shenandoah, Texas, representing more than $5 million in combined investment. The projects will modernize water metering infrastructure with near real-time usage data, hourly consumption visibility, faster leak detection, and integration with each city’s utility billing platform.
This is not a direct data-center cooling contract, but it is still relevant to the cooling side of AI infrastructure because water efficiency is becoming a practical constraint for large, heat-intensive facilities. Ameresco already serves data centers through energy infrastructure and efficiency work, and its water-management capabilities add another layer to that positioning. The Texas contracts show a municipal-scale use case for reducing water loss and improving system visibility, the same type of operating discipline that becomes more important as cooling demand rises around power-dense data centers.
Ameresco, Inc. (NYSE:AMRC) provides energy efficiency, infrastructure modernization, distributed energy, and decarbonization solutions for public, commercial, industrial, utility, and data-center customers.
3. CTS Corporation (NYSE:CTS)
Number of Hedge Funds: 23
CTS Corporation (NYSE:CTS) is one of the best small-cap data center cooling stocks to Buy. On June 16, CTS introduced the TSX Crystal with Integrated Thermistor, its first crystal product to place a thermistor inside the package. The product is not a cooling unit, but it fits the thermal-management layer around dense electronic systems: it gives real-time temperature feedback close to the crystal element, helping designers improve frequency compensation across wider operating temperatures while reducing board-level complexity.
CTS said the TSX series supports frequencies from 16 MHz to 285 MHz, with stability options ranging from ±10 ppm to ±50 ppm over temperature, and targets applications including network synchronization, routers, and switches. The data-center connection is also broader than this single launch. CTS markets temperature sensors for server racks, cooling systems, and airflow-management zones, where precise thermal monitoring helps prevent overheating and supports higher rack density. That gives the stock a sensor-level exposure to the cooling efficiency problem created by AI infrastructure.
CTS Corporation (NYSE:CTS) designs and manufactures sensors, actuators, and electronic components for industrial, aerospace/defense, medical, transportation, and other end markets.
2. Willdan Group, Inc. (NASDAQ:WLDN)
Number of Hedge Funds: 31
Willdan Group, Inc. (NASDAQ:WLDN) is one of the best small-cap data center cooling stocks to Buy. On June 1, Willdan released its June investor presentation, highlighting data-center siting and load forecasting, substation and grid design, building and energy-efficiency upgrades, and infrastructure construction support as parts of its integrated consulting, engineering, and implementation platform. The data-center cooling angle comes through efficiency and systems optimization rather than direct liquid-cooling hardware. Willdan says it works with mission-critical campuses where power and heat interact, and its data-center services include engineering, energy assessments, controls integration, procurement, and construction management.
The company also cites data-center projects where it optimized cooling systems, adjusted setpoints, improved controls, and reduced energy use, including an Evoque Data Centers project that generated 1.5 million kWh of annual savings. In AI data centers, cooling and power are increasingly connected operating constraints, so Willdan’s work in energy efficiency, utility interconnection, load forecasting, and facility systems gives it practical services-level exposure to the thermal-management problem.
Willdan Group, Inc. (NASDAQ:WLDN) provides technical, engineering, energy-efficiency, infrastructure, and consulting services to utilities, public agencies, and commercial and industrial customers.
1. TIC Solutions, Inc. (NYSE:TIC)
Number of Hedge Funds: 32
TIC Solutions, Inc. (NYSE:TIC) is one of the best small-cap data center cooling stocks to Buy. On June 1, TIC Solutions announced a repricing of its term loan, a financing move the company said would lower annual cash interest expense by about $4 million and improve financial flexibility. The development gives the company more room to support an expanded platform that now includes engineering, testing, inspection, certification, and asset-integrity services.
For the data-center cooling theme, TIC fits through the engineering and reliability layer rather than through direct liquid-cooling equipment. High-density AI facilities need better planning around heat rejection, airflow, commissioning, equipment placement, and building-systems performance, especially as rack power rises and cooling systems become more complex. TIC’s broader asset-lifecycle model gives it exposure to those infrastructure demands, making the stock a mission-critical services play tied to thermal reliability and data-center operating performance.
TIC Solutions, Inc. (NYSE:TIC) provides tech-enabled asset integrity, engineering, geospatial, testing, inspection, certification, and compliance services for industrial, infrastructure, commercial, utility, and public-sector markets.
While we acknowledge the potential of TIC to grow, our conviction lies in the belief that some AI stocks hold greater promise for delivering higher returns and have limited downside risk. If you are looking for an AI stock that is more promising than TIC and that has 100x upside potential, check out our report about the cheapest AI stock.
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