Data Center Cooling

DOWFROST™ LC 25 Heat Transfer Fluid is an inhibited propylene glycol-based coolant engineered specifically for liquid-cooled, direct-to-chip (D2C) data center applications. It is designed to efficiently remove heat from high-performance processors while helping protect cooling infrastructure from corrosion, fouling, and fluid-related reliability issues. DOWFROST™ LC 25 Heat Transfer Fluid is commonly used in technical cooling loops serving AI, HPC, hyperscale, and enterprise data centers where thermal management and system reliability are critical. The fluid is supplied pre-diluted at 25% propylene glycol concentration and is ready for immediate use.

DOWFROST™ LC 25 Heat Transfer Fluid has been formulated to support compatibility with many materials commonly used in liquid cooling systems, including copper, copper alloys, brass, stainless steel, as well as many elastomers and plastics. However, material compatibility should always be evaluated based on the specific system design, operating conditions, and original equipment manufacturer (OEM) requirements. Dow recommends consulting the DOWFROST™ LC Engineering Guide and working with equipment suppliers to confirm compatibility for a specific application.

DOWFROST™ LC 25 Heat Transfer Fluid is designed for long-term operation with minimal intervention compared to traditional treated-water cooling systems. Its fully inhibited formulation helps reduce the need for frequent chemical treatment and ongoing maintenance activities. As with any critical cooling infrastructure, Dow recommends periodic fluid monitoring to verify coolant health and system performance throughout the operating life of the data center.

Dow also supports long-term coolant management through the Dow Coolant Care Network, a coordinated network of Dow-approved laboratories, service providers, and technical specialists. It combines fluid testing, data analysis, specialist interpretation, and actionable recommendations to help operators monitor coolant condition, identify emerging issues early, and maintain consistent cooling system performance. This structured approach helps simplify coolant management while supporting reliability, uptime, and operational consistency across data centers.

For application-specific maintenance guidance, coolant health assessments, or recommendations related to your operating conditions, please contact your Dow representative or submit the Contact Us form to connect with a Dow technical specialist.

Coolant selection plays a critical role in managing operational risk and maintaining uptime because fluid performance directly impacts heat transfer efficiency, system cleanliness, material protection, and long-term reliability. Today, the two most common coolant approaches used in direct-to-chip cooling systems are Treated water and inhibited propylene glycol-based fluids (e.g. PG25). While treated water offers excellent thermal properties, it requires strict control of water quality and contamination to maintain performance over time. As a result, many operators and industry groups like Open Compute Project (OCP) recognize PG25 coolants as the standard approach as they offer a better balance between thermal performance, system protection, and operational reliability.

Using a coolant that was not specifically engineered for data center liquid cooling can introduce several risks, including corrosion, scaling, fouling, fluid degradation, biological growth, and compatibility issues with system materials. These issues can reduce heat transfer efficiency, restrict flow through cold plates and heat exchangers, increase maintenance requirements, and ultimately impact cooling performance. In direct-to-chip systems, where precise control of temperature, flow, and pressure is essential, even small changes in fluid quality can increase operational risk and lead to unplanned downtime.

In direct-to-chip (D2C) liquid cooling systems, coolant performance depends on more than just heat transfer. The propylene glycol concentration and corrosion inhibitor package play a critical role in protecting cooling infrastructure, maintaining fluid stability, and supporting long-term data center reliability. DOWFROST™ LC 25 Heat Transfer Fluid is formulated with a carefully engineered balance of both.

The 25% propylene glycol concentration in DOWFROST™ LC 25 Heat Transfer Fluid is designed to offer reliable thermal performance while offering freeze protection down to -10°C (14°F). Because the fluid arrives pre-diluted and ready to use, operators can avoid inconsistencies associated with on-site mixing and achieve consistent fluid properties throughout the cooling loop.

Equally important is the specialized inhibitor package. Direct-to-chip cooling systems commonly contain copper cold plates, brass components, stainless steel, and other metals that can be vulnerable to corrosion if the coolant is not properly protected. DOWFROST™ LC 25 Heat Transfer Fluid contains a robust corrosion inhibitor package, including protection for copper-containing systems, helping reduce the risk of corrosion, fouling, scale formation, and fluid degradation that could impact cooling efficiency and uptime.

The fluid is also manufactured using USP/EP-grade propylene glycol, with a purity of greater than 99.8%, minimizing impurities that can contribute to foaming, odors, deposits, and other maintenance challenges. This helps support long fluid life and lower maintenance requirements.

For AI, HPC, hyperscale, and enterprise data centers, selecting a coolant with the correct glycol concentration and a successful inhibitor package is essential for managing heat while helping protect valuable infrastructure. DOWFROST™ LC 25 Heat Transfer Fluid was specifically engineered for liquid-cooled data center environments to offer efficient heat removal, corrosion protection, fluid stability, and long-term operational confidence.

Recommended sampling frequency should be aligned with the customer’s risk tolerance, operating profile, and desired level of assurance. During commissioning, sampling should be more frequent until the system is fully operational, and fluid chemistry has stabilized. Once the system is fully functional, a typical approach is to continue sampling quarterly to semi-annually during the first two years of operation, then transition to annual testing if results remain stable and no material changes are made to the system or operating conditions.

Expected service life depends on the full system environment, not the fluid alone. In comparable industrial applications using DOWFROST™ Heat Transfer Fluids, they have demonstrated reliable performance for up to 10 years in secondary systems and more than 20 years in facility loops; for a well-managed direct-to-chip system, a practical planning assumption is that a flush-and-fill may be required approximately 5-7 years after installation, subject to actual operating conditions and fluid analysis. Because temperature variation, material aging, oxygen ingress, contamination, and maintenance practices can affect fluid chemistry over time, contractors and owners should ensure proper system cleaning, material compatibility, operation within Dow guidelines (DOWFROST™ LC Engineering Guide), and routine fluid monitoring to manage performance and extend service life.

Dow also supports long-term coolant management through the Dow Coolant Care Network, a coordinated network of Dow-approved laboratories, service providers, and technical specialists. It combines fluid testing, data analysis, expert interpretation, and actionable recommendations to help operators monitor coolant condition, identify emerging issues early, and maintain consistent cooling system performance. This structured approach helps simplify coolant management while supporting reliability, uptime, and operational consistency across data centers.