Which of the following represents the typical function of control valves?

The function of control valves is primarily to regulate and control the flow of fluids within a system. This involves either changing flow rates to meet system demands or isolating different sections of the piping when necessary for maintenance or operational reasons.

Control valves respond to signals from a controller, adjusting the valve opening based on the desired conditions. By changing the flow rates, they play a crucial role in maintaining optimal operation within the system, ensuring that processes can be managed efficiently and safely.

In contrast, maintaining a specific pressure, while it may involve the use of control valves in some systems, is more directly associated with pressure control equipment or pressure relief valves. Temperature readings and humidity levels are typically monitored through dedicated sensors and instruments, not directly managed by control valves.