Ontario Operator-in-Training Practice Exam 2025 – Complete Study Resource

The purpose of a pressure reducing valve is to allow water to flow from high to low pressure while regulating that flow. This is essential in plumbing systems where the incoming water pressure from the supply line may be too high for safe use or for the proper operation of plumbing fixtures and appliances. By reducing the pressure, the valve helps protect sensitive components like faucets, hoses, and irrigation fixtures from damage that could be caused by excess pressure.

Additionally, maintaining a lower and consistent water pressure can enhance the efficiency of the system, ensuring optimal performance and reducing the risk of leaks or burst pipes. The other options do not accurately describe the function of a pressure reducing valve; they pertain to different aspects of water management, such as filtration and temperature control, which are served by different types of valves and equipment in a plumbing system.