There are many heat-transfer fluids used today. 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 and deionized water, Glycol/water solutions, and Dielectric fluids.
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.
|Refrigeration System Type||Temperature Range||Heat Transfer Medium|
|Single Stage||Ambient to -20°C||water water/glycol, DI water|
|Double Stage||-20 to -80°C||Fluorinert, Galden, PAO|
|Triple Stage||-80 to -100°C||HFE-7200 or equivalent|
|Auto Cascade (air/gas)||Down to -100°C||HFE-7100 or equivalent|