Question 222Steam Plants - 1st Asst/Chief

The correct answer is C) Water hammer. Water hammer is a condition that can cause a boiler economizer to leak. Water hammer occurs when there is a sudden change in the flow of water, which can create a pressure surge that damages the economizer. This sudden pressure increase can rupture the economizer tubes or connections, leading to a leak. The other options are not directly related to causing a boiler economizer to leak. High stack gas temperatures, high feed water temperatures, and low feed water pressure may contribute to other boiler issues, but they do not directly cause the economizer to leak in the way that water hammer can.