Where is the required boiler feed water stop valve located on a high-pressure boiler?

The required boiler feed water stop valve is located between the boiler and the check valve. This placement is essential for several reasons. The stop valve controls the flow of feed water into the boiler, allowing operators to safely isolate the boiler for maintenance or during emergencies. Positioning it before the check valve ensures that the pressure in the boiler can be controlled effectively, preventing backflow of water into the feed system, which could lead to improper functioning of the boiler.

The check valve itself serves as a critical component to prevent water from flowing back into the feed line once it has entered the boiler. Therefore, having the feed water stop valve upstream of the check valve is a standard practice, helping maintain the integrity of the boiler's operation and ensuring safe conditions for the system.

In contrast, situating the stop valve in the other locations mentioned would not provide the same level of control and safety expected in a high-pressure boiler system.