Brief：1.twin-glass evacuated tubes：Reliable, efficient, High temperature resistant anti-freezing. 2.There is no water in the vacuum tube, it can still work even one tube is broken. 3. U pipe, most effi

undefinedundefinedundefinedundefinedrm into heat, pass to the fin by the tube wall, and then transfer to the U pipe by the fin, U pipe absorbs heat then transfer to medium, cold medium continuously flow into inlet and heated by U pipe ,