Abstract: Methods and devices for retaining a heating element, such as warm refrigerant tubing, within a refrigerator cabinet. Semispherical raised dimples are formed upon a retaining panel in a rolled triple flange. The dimples are intermittently positioned along the retaining panel and maintain the warm refrigerant tubing in intimate surface contact with the exterior surface panel of the refrigerator. The raised dimples preclude significant intimate surface contact between the retaining panel and the tubing and permit insulating foam to be disposed between the two so that heat transfer is minimized. A dimpled flange arrangement is also used to retain tubing within a mullion. A sheet metal insert is also described that is formed having two retaining panels with raised dimples thereupon that maintain the tubing in intimate surface contact with the exterior surface panel that forms the facing for the mullion.