Heat-transfer Fluids for Cooling Systems

There are many heat-transfer fluids used in cooling systems. Factors that determine optimal fluid selection include thermal conductivity, specific heat, viscosity, freezing point, flash point, corrosiveness, toxicity, and thermal stability. Coolants fall into three main categories: Water or glycol/water solutions, and Dielectric fluids.

Refrigeration System Type Temperature Range Heat Transfer Medium
Single Stage 7°C to 88°C Water or Water/Glycol
Single Stage -18°C to 88°C Water/Glycol
Cascade or Compound Comp. -40°C to 88°C Fluorinert, PAO, Syltherm
Cascade -73°C to 88°C Fluorinert, Syltherm

Heat-transfer fluids are selected to optimize thermal performance and maintain system life such as reducing potential for corrosion. A properly designed process chiller will ensure long-term compatibility between fluids and the materials they contact.

Contact Opti Temp for other fluids selections outside the fluids listed above. If alternative customer fluids are suggested, the specification details including density, specific heat, materials compatibility, toxicity, viscosity at the operating temperature range, and volatility are requested at time of specification.

Please note: For improved pump selection, select fluids with less than a kinematic viscosity of 20 centistokes or less over the full operating temperature range.


Second image in the first version of blog listing
Second image in the first version of blog listing
Second image in the first version of blog listing