What is the function of a mixing valve?

The function of a mixing valve is to blend hot and cold water to maintain a constant temperature. This device is essential in plumbing systems, particularly for fixtures like showers and faucets, where users desire a steady temperature without fluctuations. By adjusting the proportions of hot and cold water, the mixing valve ensures a comfortable and safe water temperature, helping to prevent scalding or discomfort due to extreme temperatures.

Other options describe functions that are not related to the mixing valve. Regulating water pressure is typically managed by pressure regulators, backflow prevention involves devices like check valves or backflow preventers, and filtering soil and debris from water is the purpose of filtration systems. Each of these functions is distinct and addresses different aspects of plumbing and water safety.