Pure refrigerant, azeotropic and zeotropic mixtures: key differences

Refrigerants can be pure substances or mixtures of two or more components.

Pure refrigerant

Has a specific saturation temperature for a given pressure.

Azeotropic mixture

Behaves almost like a pure substance and has a very small or practically negligible temperature glide.

Zeotropic mixture

The components change phase over a range of temperatures, creating a temperature glide.

Why it matters

The behavior of the mixture affects how saturation temperatures are read and service procedures.