🔍 Key Concepts

• Thermostatic control valve function in fluid systems • Temperature vs pressure control in fuel oil systems • Where precise fuel temperature matters most: storage, transfer, or at the point of use

💭 Think About

• Ask yourself: In a steam-heated heavy fuel oil system, at what point does the fuel temperature most critically affect combustion quality and viscosity? • Consider whether a thermostatic device is normally used to control temperature, pressure, or both. Which of the options actually deals with temperature control rather than pressure control? • Think about which components (storage tanks, tracing lines, or supply headers) require automatic, tight temperature regulation for proper burner/injector operation.

✅ Before You Answer

• Identify which answer choices refer to temperature control and which refer to pressure control. • Consider where incorrect fuel viscosity would immediately cause problems: in long-term storage, in tracing lines, or just before burners/injection equipment. • Verify your choice matches the usual design goal of heavy fuel heating systems: delivering fuel to the burner/injection system at a controlled temperature and viscosity.