Most designs also have a water heater in the tub to maintain proper water temperature during the wash cycle. In some designs, the heater also dries the dishes at the end of the wash. 

At the end of the "wash" cycle, the pump enters the "drain" mode. The pump drains water from the tub in one of two ways. In some "direct-reversing" designs, the motor reverses direction and a separate impeller pumps the water out. (Figure 1-A) In other designs, a solenoid-controlled valve opens to allow the pump to discharge to the drain line. (Figure 1-B) The timer controls the direction of the motor or the opening of the drain valve.