Solar water heater (SWH) is one of the technological applications that serves to produce hot water to fulfill both domestic and industry. Commonly, SWH uses solar energy, where applicated outdoor. It has a weakness that can’t describes characteristic of thermal because irradiation is fluctuating. Therefore, requires to makes a tool to facilitates research to achieve characteristic of thermal stably by SWH. The design consists mechanical and electrical. Design of mechanical consists of support frame, height control system, and tilt regulator. Then strings up design of electrical: installing lamps, cables, miniature circuit breaker (MCB), and voltage regulator. after that is testing solar simulator to set heat flux variation which is 800, 1000, and 1200 W/m2. Then testing solar simulator for SWH contains phase change material (PCM) which runs in charging while 98 minutes, where is debit variable constant as 2 LPM and heat flux as 1000 W/m2. The results of design solar simulator have main dimensions: length of 2,27 m, width of 1,73 m, and height 3 m. Lamps are used tungsten halogen within 300 W and 230 V amount of 24. SHW-PCM testing obtains highest average temperature of heat transfer fluid (HTF) is 51,1℃, meanwhile of PCM is 51,45℃. Solar simulator geos well as a source of thermal energy for SWH-PCM.