🔍 Key Concepts

• 46 CFR requirements for boiler economizers and feedwater systems • Purpose and location of stop-check valves in economizer installations • Function of a sentinel valve and where it is normally installed

💭 Think About

• Think about what happens if the economizer is bypassed while the boiler and feed system are still under pressure. Where must positive shutoff and non-return protection be ensured? • Which component in the answer choices is directly related to controlling or preventing backflow of boiler water/steam through the economizer circuit? • Consider which of the listed devices is specifically mentioned in 46 CFR in connection with economizers fitted with a valved bypass, not just boilers in general.

✅ Before You Answer

• Look up the exact 46 CFR section dealing with boiler economizers and bypass arrangements and see which valve is required at a specific location when a valved bypass is fitted. • Confirm the typical piping arrangement of an economizer: feed pump → valves → economizer → boiler. Identify where a combined stop and check function is most critical. • Verify which device (stop-check valve, emergency drain, sentinel valve) is normally associated with overpressure protection on superheaters versus flow control/non-return on economizers.