In this study, basic design data which were required for development of highly efficient ice storage system with low temperature latent heat were experimentally obtained. The ice storage system considered in this study was the one that has been widely used in the developed country and called the ice-on-coil type. Using the system, the ice storage performance for various design parameters which were the flow direction and the inlet temperature of the secondary fluid was tested. In addition, the clockwise variation of the heat transfer characteristics of the PCM in the ice storage tank were investigated. During the melting processes in the ice storage tank with several vertical tubes, decrease of the solid-liquid interface area, which was the heat transfer area, between the floating ice and the water made the decreasing rate of IPF less. Also, the total melting energy for the upward flow of the secondary fluid was higher than that for the downward flow during the melting process, but this trend did not appear if the initial temperature of the PCM was $4^{circ}C$. The average ice recovery efficiency for the upward flow of the secondary fluid was higher than that for the downward flow.