What is a Cascade Refrigeration System? All You Need To Know The cascade refrigeration system is a freezing system that uses two kinds of refrigerants having different boiling points, which run through their own independent freezing cycle and are joined by a heat exchanger. The schematic view and the P-h diagram of this system are shown below. This system is employed to obtain temperatures of -40 to -80°C or ultra-low temperatures lower than them. At such ultra-low temperatures, a common single-refrigerant two-stage compression system limits the low-temperature characteristics of the refrigerant to a considerably poor level, making the system significantly inefficient. The efficiency is improved by combining two kinds of refrigerants having different temperature characteristics. Here are the key points to understand about cascade refrigeration systems: Basic Concept 1. *Two or More Stages*: The system is divided into stages, each operating at different t...