Each refrigerant has its own properties and these properties are compiled on the pressure enthalpy chart for that particular refrigerant.
The pressure enthalpy chart enables us to create a complete picture, or “snapshot” of the entire system. With a completed pressure enthalpy plot, we
can evaluate the major system components as well as calculate latent and sensible heat transfers.
The book starts by reviewing the basic vapor-compression refrigeration cycle, as well as the concepts of superheat, sub-cooling and the pressure/ temperature relationship.
The book then turns to the pressure enthalpy chart, giving an overview of the meaning and purpose for every line on the chart. Simplified charts are used to clarify the explanations.
The plotting of actual systems follows next. The completed plot allows for the evaluation of various system parameters and the calculation of many system characteristics, including system
capacity and system efficiency.
It is during this evaluation process that system problems can be easily identified.
Once the concepts of pressure enthalpy have been mastered, the reader can truly appreciate this tool and its usefulness to effectively and accurately
start up, troubleshoot and evaluate air conditioning and refrigeration systems.