This paper presents a study of heat exchanger design for improving the performance of ice maker by using waste water from ice factory. The heat exchanger was made of stainless steel and had 4.023 m2 of heating surface. After using the heat exchange in the waste water pond which the temperature was 0 C the temperature of feed water was decreased from 28 C to 22 C. The COP of the ice maker was increased and the factory can save energy consumption 52034 kWh/year or 61993 baht/year. The payback period was 0.5 year

This study was aimed to investigate experimental study of the parameters affecting the amount of tubular ice. Significant studied parameters were inlet water temperature. Thickness tendency was increasingly according to time. The thickness of the tubular ice varies with the square root of time according to the theory. At the beginning of the process thickness increased quite fast and decelerated at the end of the production process. The inlet water temperature affected to thickness of tubular ice as the ratio of inlet water temperature to thickness was 0.41 degrees Celsius per millimeter. Thus inlet water temperature affected to thickness of tubular ice according to theoretically results with 342% 43% and 8% error value between ice thickness and production time for 0-10 minutes 11-20 minutes and 21-36 minutes respectively