Clean water is a very important, basic need of life; therefore, its sources must be researched and developed. The vast amount of water vapour present in a warm and humid atmosphere could be a potential water source. In this study, a new atmospheric water generator (AWG) was designed and tested. The system consists of a window air conditioner and an attachment. It was made at a local workshop from food-grade 304 stainless steel This attachment completely converted the air conditioner to an AWG. The system was tested under warm and humid climatic conditions in the coastal town of Rayyis, Saudi Arabia. The performance of the system was compared with the performance of three commercial units. The best water harvesting rate and the energy consumption rate, at an 81-86% relative humidity and 30-29 C, were 0.7 L/h and 1.02 kWh/L, respectively. This comparison shows that the developed system has potential as a commercial product.