Hello OnTheGo51! For optimum performance, the dishwasher should be connected to a 120°F (49°C) hot water supply. While the actual water heater is responsible for heating water before it enters the dishwasher, the heating element is a supplemental tool that serves several different purposes. Most modern-day dishwashers operate at a temperature between 130 to 170 degrees Fahrenheit. Water entering the dishwasher has an average temperature of 120 degrees Fahrenheit, which may or may not properly sanitize the dishes. The heating element, however, warms the water up by an additional 10-15 degrees; thus, effectively killing harmful bacteria and germs. In addition to killing bacteria, the dishwasher’s heating element serves a second purpose: to encourage faster and more efficient drying times.