1.solar water heater CE approved. 2.15 Years Warranty 3.Pre-assemble. 4.OEM solar water heater system solar water heaterIt ... down 3~5°C per dayOptional accessories: assistant tank, electric heater, reflector ,automatic inlet water valve, Magnesium anode, ect. ... the air, only 1/4 electricity consumption of electrical water heater 2) Utilizing high efficiency, environment protecting working substance 3 ...