Energetic Assessment of an Electronic and a Thermostatic Expansion Valve for a Variable Capacity Compressor


  • Orhan Ekren Ege University-Solar Energy Institute, 35100 Bornova, Izmir, Turkey




Electronic expansion valve, thermostatic expansion valve, variable speed compressor, superheat control, energy saving.


 In this study, a chiller system with an electronic expansion valve (EEV) and a thermostatic expansion valve (TXV) were compared from an energy saving view under variable and fixed speed compressor. The experimental chiller system under study has a variable speed scroll compressor, EEV and TXV, air cooled condenser and auxiliary equipments. The R134a was used in the compressor as a refrigerant. Although in variable speed chiller systems usually EEVs are used, in this study a TXV was also used to compare its performance. The results of the experimental studies show that the chiller system with EEV has 30% lower superheat value and 6% lower power consumption than the chiller system with TXV under variable speed operation. From the fixed speed compressor view, the chiller system with TXV performs 1.7% lower superheat value than the chiller system with EEV and, the chiller system with EEV has 8.5% higher compressor power consumption than TXV.


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How to Cite

Orhan Ekren. Energetic Assessment of an Electronic and a Thermostatic Expansion Valve for a Variable Capacity Compressor. J. Adv. Therm. Sci. Res. [Internet]. 2019Oct.25 [cited 2021Sep.26];6(1):51-7. Available from: https://www.avantipublishers.com/jms/index.php/jatsr/article/view/880