Abstract: A washing machine includes a tub having a water collecting well, a water suply conduit provided with a controllable valve for supplying water to the well during at least one water supply phase of the operation of the washing machine, and a circulation pump for circulating water collected in the well during at least a latter portion of the supply phase. A control system automatically controls operation of the valve and thereby the supply of water to establish a minimum water level within the well required for optimum operation of the circulation pump. The control system includes a control chamber and an overflow wall having a predetermined overflow level and communicating the well with the control chamber, such that when the level of water in the well reaches the overflow level the water overflows the overflow wall into the control chamber.