Solar Water Heater (SWH) is a solar water heater utilizing solar energy. Solar Water Heater (SWH) has a storage medium in the form of water that has a low energy density that happens in the need for a large volume of TES (thermal energy storage) tank. On the other hand, PCM (phase change material) has a high energy density value and has good thermal properties. Based on the characteristics of the PCM, an experimental study of paraffin wax on a Solar Water Heater (SWH) system is needed. The goal of this study is to design test equipment and determine the results of the charging and discharging process to determine thermal energy storage in the design of the TES tank. the design and manufacture of TES tanks begins with determining the intensity of sunlight, thermosyphon discharge, stagger pipe arrangement with a 45 angle and tube pitch. Furthermore, the selection of pump specifications, rotameter devices, heater power, tank capacity, number of capsules used, and charging and discharging tests on the voltage and discharge variations are given so that the temperature evolution can be seen at each cross-section. The effects showed that the design of the TES tank has supporting devices when testing such as a 12 volt DC pump, rotameter charging 1000 mLPM while discharging 3 LPM, heater power of 1500 Watts using immersion heaters, 60 liter tank capacity, 32 capsule pipes, and the results of charging variation of 227 Volts and 2.5 LPM discharging has the best results in the vertical direction with a regular temperature drop.