Heating Element's Purpose
When water first enters a dishwasher, it is cold. It is the heating element's job to warm the water up so it can clean the dishes. This heating element is built into the bottom of the dishwasher, and may or may not be visible when the dishwasher is opened. It is a tube-like device usually arranged in a circle or wave pattern, and is most often metallic or black in color. Some dishwashers keep their elements hidden underneath a panel or in the back of the washer where they cannot be seen.
Regardless of its position, the element is used to heat incoming water until it can be pumped into the washing mechanism. Most dishwashers have sensors that automatically detect the temperature of the water so it can be used only when it is hot enough. Heating elements are designed to heat water to around 140 or 150 degrees Fahrenheit, the temperature scientifically proven to thoroughly clean dishes. If the heating element does not bring the water up to that temperatures range, it is not operating effectively.
When the dishwasher is turned on, water is pumped in from an outside source and deposited into the heating element's chamber or cavity. The heating element, no matter what shape it has, is connected with two prongs at either end into the inner circuitry of the dishwasher. Like an electric oven circulates electricity to heat burners, so the heating element runs a current of electricity between one inserted prong and the other. This electricity heats the metal, which in turn heats the surrounding water. Once the water is hot enough, it is pumped into jets that spray it from various locations in the dishwasher as part of the cleaning process.
The dishwasher may also have a secondary heating element. While only one heating element is needed to heat the water, the second heating element may be used to help warm or dry the dishes. In this case, the element heats surrounding air, which is then blown through a fan onto the dishes.