Which two types of valves are required on the feedwater piping to the boiler?

The requirement for both a check valve and a stop valve on the feedwater piping to the boiler is essential for the safe and efficient operation of the system.

A check valve is crucial because it allows the feedwater to flow in one direction towards the boiler, preventing backflow. This backflow could lead to contamination of the water supply or pressure fluctuations that can negatively impact boiler operation. By preventing backflow, the check valve helps maintain system integrity and ensures that the boiler operates with the necessary water levels and pressure.

The stop valve, on the other hand, serves a different but equally important purpose. It is used to isolate the boiler from the feedwater system when maintenance or servicing is required. Being able to quickly shut off the flow of water ensures that technicians can safely perform their work without risking injury or causing damage due to unexpected water flow.

Together, these two types of valves create a safe and controlled environment for the boiler's operation, making them a standard requirement in boiler feedwater systems.