🔍 Key Concepts

• Understand how a two-element feed water regulator differs from a single-element regulator • Consider what second variable (besides drum water level) best reflects boiler load changes • Think about which choice would provide a direct, fast signal of changing steam demand

💭 Think About

• Ask yourself: When steam demand suddenly increases, what variable changes first and can be measured easily to adjust feedwater? • Which option would help the regulator maintain drum level by anticipating level changes, not just reacting after the level has already shifted? • Which of the listed signals is commonly used in automatic boiler control systems as a measure of load?

✅ Before You Answer

• Identify which choice is most directly tied to boiler steam load rather than a secondary effect • Eliminate any options that are more like outputs or consequences of control action instead of true load indicators • Verify which signal is typically paired with drum level in standard two-element feedwater control diagrams in your engineering texts