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

The correct choice of gravity tank auxiliary pressure serves a critical purpose when the public water supply main is deemed insufficient. This method involves the use of a storage tank situated at a height, allowing gravity to generate pressure. Consequently, water can be distributed effectively throughout the plumbing system, ensuring a steady supply even when the public main cannot meet the demand. Gravity tanks can store and maintain water pressure during peak usage times, facilitating a reliable and consistent flow.

In contrast, other options may not address the specific issue of insufficient main pressure effectively. For instance, a boiling water system is primarily for sanitizing water but does not contribute to pressurizing or supplementing the supply itself. Gravity filtration might help in purifying water but does not enhance the pressure or volume of the water supply. A pressurized air system typically works in conjunction with other systems to assist in water distribution but is not a direct supplement or source of additional water supply. Therefore, gravity tank auxiliary pressure is the most suitable solution in the context of addressing insufficient public water supply.