Most modern dishwashers are equipped with a built-in heater, so you do not need to bring hot water to the sink before starting the dishwasher. The dishwasher's internal heating element is designed to heat the water to the required temperature for efficient cleaning and sanitization.
Here's how the process typically works:
Water Inlet: When you start the dishwasher cycle, the dishwasher's water inlet valve opens, allowing cold water to enter the dishwasher.
Prewash: During the initial prewash phase, some dishwashers may use cold water to rinse off loose debris from the dishes.
Main Wash: After the prewash, the dishwasher will use a combination of hot water from the internal heater and the incoming cold water to reach the desired wash temperature. The built-in heater will heat the water to the necessary temperature for effective cleaning, usually around 120-140°F (49-60°C).
Rinse Cycle: In the final rinse cycle, hot water is again used to ensure proper sanitization and to aid in drying the dishes.
The presence of a built-in heater in dishwashers is especially useful in households where the hot water supply might not be consistent or might not reach high enough temperatures for effective dishwashing. The dishwasher's internal heater ensures that the water used for cleaning reaches the optimal temperature regardless of the hot water supply.
However, if you want to maximize the efficiency of your dishwasher, you can help by running your kitchen faucet until the water becomes hot before starting the dishwasher. This reduces the time the dishwasher needs to spend heating the water, potentially shortening the overall cycle and saving energy. But even if you don't pre-run your faucet, the dishwasher's internal heater will still heat the water to the required temperature for proper cleaning and sanitization.