What is one of the main purposes of using a check valve in boiler feedwater systems?

The primary function of a check valve in boiler feedwater systems is to prevent backflow. This is crucial because backflow can lead to contamination of the feedwater supply, potential boiling hazards, and can cause damage to the boiler system. The check valve allows water to flow in one direction only, ensuring that once the feedwater enters the boiler, it cannot flow back into the feedwater system or other connected lines. This mechanism is essential for maintaining the integrity of the system and ensuring effective operation of the boiler while protecting it from any adverse effects of reverse flow.

Other options, while they pertain to aspects of boiler systems, do not accurately describe the function of a check valve. Increasing water pressure, regulating water temperature, and measuring water levels are functions managed by different components in the system, such as pumps, temperature sensors, and level gauges, rather than the check valve itself.