31/03/2026 by gpihl
Organic, colourless and odourless, glycol is a viscous compound that belongs to the alcohol family.
In heat transfer systems, glycol is mainly used as an antifreeze because it can effectively lower the freezing point of system fluids that have a water base. This can prevent unwanted incidents under cold operating conditions, like frozen or burst pipes.
However, glycol has other useful characteristics, and can serve a coolant, mitigate scale formation and inhibit corrosion. This leads to multiple positive outcomes including enhanced thermal stability, equipment protection and the facilitation of efficient and safe heat transfer in both cooling and heating systems.
Effective freeze protection
When glycol and water are mixed, the emulsion prevents freezing. This is crucial for machinery and pipes fitted in heating, ventilation and air conditioning (HVAC) systems and commercial and industrial chillers, preventing them from becoming damaged while operating at low temperatures.
Inhibiting corrosion
When glycol-based fluids are engineered, their formulation typically creates additives called “anti-corrosion inhibitors”. These stop metal parts deteriorating and can increase the active service life of critical system components like heat exchangers and industrial pumps.
Advanced low and high temperature operations
Glycol-based fluids offer operators an extended temperature range. They let systems run at well below 0°C without water turning to ice, but also serve as a stable heat transfer fluid (HTF) when working at higher operating temperatures.
Enhanced system efficiency
Creating a stable, heat transfer medium in liquid form, glycol is employed in multiple industrial processes, including cooling data centres, as it can ensure dependable performance even when fluctuations in temperature occur.
Key considerations when using glycol
It’s important to note that there are two main glycol types that are suited to different applications.
Propylene glycol is often employed in manufacturing environments producing pharmaceuticals, food and beverages due to its lower toxicity compared to other glycol-based fluids. Ethylene glycol, however, is a more popular choice for industrial applications because it is 20 to 30 per cent less expensive than propylene glycol.
It is also worth remembering that while it can protect pipes and parts from freezing, glycol is not as efficient as pure water when it comes to transferring heat, so it can require higher flow rates.
For glycol-based fluids from leading brands like Fuchs and CPI Fluid Engineering, browse our product selection or contact us for further information.
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