The basic refrigeration cycle and the typical pressure behaviour of common refrigerants used in air-conditioning and refrigeration systems. It explains how refrigerant changes pressure, temperature, and physical state as it moves through the main components: compressor, condenser, expansion valve, and evaporator.
The cycle begins at the compressor, where low-pressure refrigerant gas is compressed into a high-pressure, high-temperature gas. This gas then flows to the condenser, where heat is released to the outside air and the refrigerant changes from gas into liquid. After that, the refrigerant passes through the expansion valve, where its pressure is reduced and the flow is controlled. The low-pressure liquid then enters the evaporator, where it absorbs heat from indoor air and changes back into gas, producing cooling effect before returning to the compressor.
The lower table provides a general pressure reference for several refrigerants such as R22, R134A, R600A, R32, R290, R407C, R404A, R410A, and R417. It compares their standing pressure, suction pressure, discharge pressure, and boiling temperature.
