Volume V, Issue IV, April 2016 IJLTEMAS ISSN 2278 – 2540 www.ijltemas.in Page 106 Influence of Electronic Expansion Valve on the Performance of Window Air Conditioner Retrofitted With R407C E.Devandiran 1 , V. S. Shaisundaram 2 , S. Shyam Sundar 3 , C. B. Selva Subramaniam 4 , P. Nsamu Shihabudeen 5 1 ,2 Assistant Professor , Department of Mechanical Engineering, Easwari Engineering College, Chennai, Tamil Nadu, India. 3,4,5 U.G.Student , Department of Mechanical Engineering, Easwari Engineering College, Chennai, Tamil Nadu, India Abstract: The object of this experimental study is to investigate the effects of the expansion devices on the performance of a one TR window air conditioner retrofitted with eco friendly alternative refrigerant R-407C. The widow air conditioner applying the expansion devices of a capillary tube, thermostatic expansion valve and electronic expansion valve is tested by varying changing condenser temperature from 40 0 C to 55 0 C, while maintaining evaporator temperature at 6 0 C. The R 22 capillary tube system is utilized as baseline unit for the performance comparison with the R-407C system. The capacity for the R407C EEV system is higher by 10.1% at full charge condition than that for the R22 capillary tube system. The capacity for the R407C EEV system is higher by 10.2% at full charge condition than that for the R407C TEV system. The COP of R407C EEV system is higher by 15.4% and 12.3% than that of R407C capillary tube and thermostatic expansion valve respectively. The final result show an overall better performance of the electronic expansion valve compared with the thermostatic expansion valve and capillary tube. Keywords: Window air conditioner; Capillary tube; Thermostatic expansion valve; Electronic expansion valve; R- 407C. Nomenclature COP - Coefficient of performance. TEV - Thermostatic expansion valve. EEV - Electronic expansion valve. TR - Tonne of refrigeration. BIS - Bureau of Indian Standard. I. INTRODUCTION FC (chlorofluorocarbon) and HCFC (hydrochlorofluorocarbon) refrigerants as refrigerants in a vapor compression refrigeration system are known to be the principal cause of ozone depletion and global warming, production and use of these refrigerants have hence been restricted [1].As a result, a search for alternative refrigerants that fit the requirements in an air-conditioner or a heat pump has been underway. Refrigerant mixtures which are composed of HFC (hydrofluorocarbon) refrigerants having zero ODP (ozone depletion potential) are now being suggested as drop- in or mid-term replacement. An air-conditioning system based on these new alternative refrigerants must be modified or redesigned because thermophysical properties of these alternative refrigerants differ from those of conventional refrigerants. In order to maintain or improve the performance of the cycle, the operating characteristics of individual components of the cycle should be redefined with these new alternative refrigerants. It has been reported that R407C is a close match to R22 with respect to energy efficiency. The thermo physical properties of R22 and R407C are shown in tab.1. The type an electronic expansion valve (EEV) considered is a solenoid valve linked to an electronic controller. The operation of electronic controller is based on four temperatures, the refrigerant at inlet and outlet of evaporator and on the air inlet and outlet of air cooled evaporator measured by means of thermoresistances. An EEV is a variable area expansion device, which is commonly used in small refrigeration and air conditioning systems. The flow inside EEV is very complex and pressure drop through the EEV has a strong influence on the performance of the whole system. Table 1- Thermo- physical properties of selected refrigerants Properties Refrigerants R-22 R-407C Molecular weight [g/mol] 86.5 86.2 Normal boiling point [ o C] -40.9 -43.6 Critical temperature [ o C] 96.2 86.7 Critical pressure [bar] 50.5 46.2 C