Several investigations have emphasized process parameters of single-effect vapour absorption system; yet, the influence of process parameters on thermodynamic performance of the absorption system has not been focussed for the best performance conditions. Several process parameters such as absorber, generator, evaporator, and condenser temperatures influence an absorption refrigeration s ystem’s e xergetic and energetic performance. In t he present study, the design of experiments has been used for the optimization of process parameters. A 1.5 kW cooling capacity of the LiBr-H2O absorption system has been developed and tested under various operating conditions. Performance characteristics such as in COP and heat dissipated by the condenser (Qc) of the ARS system have been studied at different ranges of operating parameters. For the process parameter optimization, a central composite design under Response Surface Methodology has been used. The maximum COP and Qc have been obtained as 0.827 and 2488.79, respectively at optimum values of generator temperature (Tg) = 95.1 oC, condenser temperature (Tc) = 45.3 oC, absorber temperature (Ta) = 28.4 oC and evaporator temperature (Te) =15 oC. The optimum conditions obtained by the design of experiments have been validated through experiments on the ARS system, and experiments have been conducted at closer conditions of the optimized values of the operating parameters and found the maximum COP and Qc as 0.926 and 2518.01, respectively. The results of this paper have been very u seful i n d esigning a better vapour absorption system.