Which of the following is NOT a type of valve used in pool systems?

The correct answer is that a spring is not a type of valve used in pool systems. In pool applications, valves play a crucial role in controlling the flow of water throughout the system. Wafer valves, rotary multiport valves, and gate valves are all commonly utilized in pool plumbing and filtration systems.

Wafer valves are designed to be light and easy to install in tight spaces, providing an effective means to manage water flow. Rotary multiport valves are essential for facilitating different functions such as filtering, backwashing, rinsing, and draining the filter. Gate valves are often used to start or stop the flow of water, providing a straightforward on/off control.

A spring, on the other hand, is generally not classified as a valve. While springs can be components within actuators or certain mechanical devices in broader systems, they do not function as standalone valves to control water flow in pool systems. This distinction highlights that while springs play a role in mechanical systems, they do not serve the specific function of regulating water flow in pool operations.