🔍 Key Concepts

• Function of a contaminated drain inspection tank in a boiler or fuel system • What leaks from steam-side equipment versus what leaks from fuel-side equipment • How a fuel oil heater is constructed (tube side vs. shell side) and which fluid is on each side

💭 Think About

• Think about which component has fuel oil on one side and another fluid (usually steam) on the other, and which side normally drains to the contaminated drain tank. • Ask yourself: if this part leaks internally, which fluid will end up in the drain system that is monitored as "contaminated"? • Eliminate any choices where a leak would drain either to a different system or be obvious somewhere else (like visible external leakage).

✅ Before You Answer

• Identify which option(s) involve heat exchangers with separate steam and fuel spaces. • Confirm which equipment has its drains led to the contaminated drain inspection tank in a typical marine boiler/fuel system arrangement. • Verify which leak would cause fuel oil to migrate into a steam condensate or drain line, rather than steam entering the fuel system.