Abstract: A support system is provided for a bundle of U-shaped tubes in a heat exchanger of the shell and tube type. The system includes a fixed frame including a plurality of support plates for the majority of the length of the bundle and a floating frame including a plurality of support plates for the U-bend end of the bundle. The floating frame is mounted on the tubes and is free to move relative to the fixed frame, thus allowing freedom of expansion of the tubes through the fixed frame support plates even on the occurrence of tube binding in the floating frame support plates adjacent the U-bend end.