Experimental assessment of R134a and its lower GWP alternative R513A

Lower GWP refrigerants are essential to mitigate the impact of refrigeration systems on climate change. HFO/HFC mixtures are currently considered to replace HFCs in refrigeration and air conditioning systems. The aim of this paper is to present the main operating and performance differences between R513A (GWP of 573) and R134a (GWP of 1300), the most used refrigerants for medium evaporation temperature refrigeration systems and mobile air conditioners. To perform the experimental comparison, 36 tests are carried out with each refrigerant at evaporating temperatures between −15 and 12.5°C and condensing temperatures between 25 and 35°C. The conclusion of the experimental comparison is that R513A can substitute R134a with only a thermostatic expansion valve adjustment, achieving better performance and higher cooling capacity. The discharge temperature of R513A is always lower than that of R134a.The authors thankfully acknowledge the Ministry of Education, Culture and Sports, Spain for supporting this work through “Becas y Contratos de Formación de Profesorado Universitario del Programa Nacional de Formación de Recursos Humanos de Investigación del ejercicio 2012 (Grant number FPU12/02841)” and “Ayudas complementarias para beneficiarios de ayudas (FPU): Estancias Breves. Convocatoria 2015 (Grant number EST15/00154)”. This research is also done within the Effsys Expand P08 project that is funded by the Swedish Refrigeration Cooperation Foundation, KYS and Swedish Energy Agency with the support of Bosch Thermoteknik AB, Danfoss Värmepumpar AB, Nibe AB, Nowab, Svensk Energi & Kylanalys AB and Svenska Kyltekniska Föreningen