Efficient cooling equipment, no matter how advanced, cannot compensate for poor water chemistry. When water quality is not properly managed, performance and reliability suffer leading to multiple consequences (e.g., shortened service life, increased chance of an LTI, and the risk of downtime). Scale formation, for instance, acts as an insulating barrier on heat transfer surfaces, significantly reducing thermal efficiency and increasing energy demand. Corrosion further compounds the issue by degrading system components, shortening equipment lifespan, and increasing the likelihood of leaks and failures. At the same time, biofouling—driven by uncontrolled microbiological growth—adds resistance to the heat exchange process and forces fans and pumps to work harder, raising operational costs.
Because of these impacts, water treatment should be viewed as an integral part of thermal system design rather than a secondary maintenance consideration. At Toepfer & Associates, PLLC, we begin with a thorough characterization of the source water, identifying key constituents such as hardness, alkalinity, silica, and dissolved solids. From there, water quality limits are established for each loop within the system, ensuring that operating conditions remain within controlled and predictable ranges.
Equally important is aligning the treatment strategy with the materials of construction. Different metals and polymers respond uniquely to water chemistry, so corrosion control programs must be carefully tailored. System design also emphasizes the stabilization of key parameters such as conductivity and pH, while maintaining a vigilant approach to corrosion potential and microbiological risk.
In evaporative cooling systems, increasing cycles of concentration can deliver meaningful water savings by reducing blowdown. However, this benefit is only realized when scaling ions, silica deposition, and biological activity are effectively managed. Without proper control, attempts to increase cycles can quickly lead to fouling and system inefficiencies that outweigh any water savings. In closed-loop or liquid cooling systems, the margin for error is even smaller, requiring tighter control of fluid chemistry to preserve clean heat transfer surfaces and consistent performance.
References:
American Society of Heating, Refrigerating and Air-Conditioning Engineers. (2021). Thermal guidelines for data processing environments (5th ed.). ASHRAE.
Lei, N., Lu, J., Shehabi, A., & Masanet, E. (2025). The water use of data center workloads: A review and assessment of key determinants. Resources, Conservation and Recycling, 219, 108310. https://doi.org/10.1016/j.resconrec.2025.108310
Mytton, D. (2021). Data centre water consumption. npj Clean Water, 4, Article 11. https://doi.org/10.1038/s41545-021-00101-w
NREL. (2024). Data center best practices for energy and water performance. National Renewable Energy Laboratory. https://www.energy.gov/sites/default/files/2024-07/best-practice-guide-data-center-design_0.pdf
Ristic, B., Madani, K., & Makuch, Z. (2015). The water footprint of data centers. Sustainability, 7(8), 11260–11284. https://doi.org/10.3390/su70811260