The log p-h diagram in a refrigeration cycle typically shows three key regions: the liquid region, the boiling region, and the gaseous region. The liquid region represents the refrigerant’s state during the condensation process, while the boiling region represents the refrigerant’s state during the evaporation process. The gaseous region represents the refrigerant’s state during the compression process. The diagram may also show the mixed forms of these regions, such as the liquid-gas mixture during the expansion process.