At what point must the stop valve be positioned in relation to the boiler outlet?

The stop valve must be positioned as close as practicable to the boiler outlet to ensure optimal control over the flow of water or steam from the boiler. This close proximity facilitates quick and efficient operation should it be necessary to isolate the boiler from the system for maintenance or emergency shutdowns.

By having the stop valve positioned near the boiler, it minimizes the length of pipe that needs to be drained or filled when performing maintenance tasks, which can save time and reduce the volume of fluids that may need to be handled. Additionally, this arrangement helps to prevent potential issues such as water hammer and improves safety, as operators can easily access the valve in case of an emergency.

The choice of positioning further aids in maintaining proper pressure and temperature control right at the boiler, enhancing the overall efficiency of the system. This design consideration is crucial for ensuring the reliability and safety of hydronic and process piping systems.