In most dishwashers, the upper tub or rack does not have a separate heating mechanism. The heating element in a dishwasher is typically located at the bottom of the tub, below the lower rack. It is responsible for heating the water during the wash and rinse cycles.
The heating element in a dishwasher is usually an electric heating element. When the dishwasher is in operation, the heating element is energized, and electricity passes through it, generating heat. This heat is transferred to the water in the dishwasher, raising its temperature and aiding in the cleaning and drying processes.
As the water circulates during the dishwasher cycle, the hot water rises to the upper tub or rack through the spray arms and nozzles. This ensures that the dishes on both the upper and lower racks are exposed to the heated water, allowing for effective cleaning and sanitization.
It's important to note that the upper tub or rack itself does not have a dedicated heating mechanism. The heat is primarily generated at the bottom of the dishwasher and then circulated throughout the appliance to provide consistent temperature throughout the cleaning process.