Abstract: A water heater tank arrangement, control device and shaft extension therefor and methods of making the same are provided, the water heater tank arrangement comprising a water heater tank having a heating unit therefor, a control device carried by the tank and having an operating unit to sense the temperature of the tank and to operate the heating unit in relation to the sensed temperature and a selected temperature of the control device, the control device having a housing and having a temperature selector unit rotatably carried by the housing to set the selected temperature, the selector unit comprising a knob provided with a transverse slot therein, and a shaft extension having opposed ends one of which has drive structure snap-fitted into the slot so that the knob is adapted to be rotated upon the turning of the other of the ends of the shaft extension.

Abstract: A water heater tank arrangement, control device and shaft extension and the methods of making the same are provided, the water heater tank arrangement comprising a water heater tank having a heating unit, a control device carried by the tank and having an operating unit to sense the temperature of the tank and to operate the heating unit in relation to the sensed temperature and a selected temperature of the control device, the control device having a housing and having a temperature selector unit rotatably carried by the housing to set the selected temperature, the selector unit comprising a knob provided with a transverse slot, and a shaft extension having opposed ends one of which has drive structure snap-fitted into the slot so that the knob is adapted to be rotated upon the turning of the other of the ends of the shaft extension.