Illinois Plumbing Code Practice Exam 2025 – All-in-One Guide for Exam Success!

The correct answer emphasizes the importance of the temperature sensing element's correct immersion depth to ensure accurate temperature readings for proper functioning of the temperature relief valve. For a storage water temperature of 210 degrees Fahrenheit, the sensing element must be positioned to accurately reflect that temperature for the valve to operate effectively. This is crucial for the safety and performance of the water heating system, as it prevents overheating and potential pressure build-up.

Options suggesting different depths or temperatures would likely lead to inaccurate readings or a malfunction of the relief system. For instance, positioning the sensing element at 4 or 6 inches with a corresponding lower temperature would not provide the necessary information about the water's actual temperature, risking safety compliance and system integrity. Similarly, a depth of 8 inches with a higher temperature would not align with the requirement for a precise 210 degrees storage temperature, again compromising performance and safety.