🔍 Key Concepts

• Duplex fuel oil strainer operation and purpose • What a large differential pressure across a strainer usually indicates • Effects of changing pump discharge pressure or boiler firing rate on the fuel system

💭 Think About

• What does a big difference between inlet and outlet pressure across a strainer tell you about the condition of the strainer? • Which action would directly address a restriction in the strainer without disturbing normal boiler operation? • Would securing the pump or changing firing rate fix the cause of the high differential pressure, or just create other problems?

✅ Before You Answer

• Verify that high differential pressure across a strainer usually means it is becoming clogged or dirty • Confirm which option allows you to restore normal flow while keeping the fuel system and boilers operating properly • Eliminate any choices that do not correct the cause of the abnormal pressure readings (e.g., only change demand or shut things down)