A supporting frame and thin stave cooler for a metallurgical furnace comprises a metal structure fastened to the cold face of the thin stave cooler that adds strength and rigidity. The thin stave cooler itself is lightened, thinned, and simplified to take optimal advantage of the supporting frame and its provisions for mounting and attaching the thin stave cooler assembly to the inside walls of a furnace containment shell. Water is circulated in the thin stave cooler through feed and discharge piping connections that pass through the supporting frame and are sleeved by protection sleeves. The protection sleeves can serve as a primary or secondary support system when they are welded between the furnace containment shell and the supporting frame when first installed.