The main control valve on a sprinkler system is located between which two components?

• A. Riser and Branches
• B. Source of Water Supply and the Sprinkler System
• C. Cross Mains and the Riser
• D. Fire Department Connection and the Riser

Answer: (B)

The main control valve is the shutoff for the entire sprinkler system, so it must be placed right at the point where water enters the system. That means it sits between the source of water supply and the sprinkler piping. Placing it here allows you to isolate all the system piping with one valve, which is essential for maintenance or emergencies. If the valve were located downstream on a branch, the entire network could still receive water, defeating the purpose of a single isolation point. It’s not the valve between internal distribution components like cross mains and the riser, or between the fire department connection and the riser, because those valves serve different parts of the system’s distribution rather than controlling the overall supply.