We are the one of the manufacturing leader of solar-water-heater and heat-pump-water- heater system. after a decade of research and development, centech system co. ltd., have the patent of "no scaling heat exchange technology. this is a joint venture with new energy center of national taiwan university. we successfully developed a number of patent portfolios to adapt to the environment of solar appliance products. i look forward working with you. please do not hesitate to contact me with any questions or concerns.