Which of the listed order of valves...

🔍 Key Concepts

• Feedwater regulator function and where it should be located relative to the boiler drum and the main stop valve • Purpose of a stop valve versus a stop-check valve on boiler feed lines • Which valve must be able to prevent backflow from the boiler into the feed line if a line parts or a pump fails

💭 Think About

• Think about the direction of water flow: from the feed pump toward the boiler. In what order do you want to control flow, regulate level, and prevent reverse flow? • Which valve do you want located closest to the boiler so that the boiler cannot drain back through the line? • Where should the automatic control device (regulator) be placed so it can sense and control boiler water level effectively without being isolated when the line is shut down?

✅ Before You Answer

• Identify which valve type is specifically designed to serve as both a stop valve and a check valve and therefore is usually installed right at the boiler inlet • Confirm that the regulator must be installed so that it is not rendered useless whenever the main stop is closed for isolation • Make sure the arrangement allows you to first isolate the line, then automatically control flow, and finally prevent backflow from the boiler into the feed system

Which of the listed order of valves represents the proper installation of the main feedwater supply line to a marine propulsion boiler?

Regulator, stop, stop-check

Stop, regulator, stop-check

Stop-check, regulator, stop

Stop-check, stop, regulator

🔍 Key Concepts

💭 Think About

✅ Before You Answer