solar water heater, pressurized, easy installation, economical, save money, ... water heaterSG-S serials is Thermosyphon solar water heater, That is a kind of solar water heating ... Temperature when exposed to sun without water: 250°C, 2.5 hours to boiling point if using single ... The temperature go down 3~5°C per day7) Optional accessories: assistant tank, electric heater, reflector ,automatic inlet water ...