A method of controlling a washing machine. The washing machine includes a tub configured to receive water, a drum rotatably disposed in the tub, a volute pump including (i) an impeller configured to rotate in one or more directions to pump water discharged from the tub and (ii) a pump housing that defines a volute-shaped passage configured to guide water pumped by the impeller, and a circulating water supply device configured to supply water discharged from an outlet port of the volute pump into the drum. The method includes: supplying water and detergent into the tub; and rotating the impeller of the volute pump in a first direction to discharge a first amount of water from the volute pump, the first amount of water being less than a second amount of water discharged from the volute pump based on the impeller being rotated in a second direction.