Minnesota Special Engineer Boiler License Practice Exam

What is the primary purpose of a check valve on a feed water line to a steam boiler?

1. To allow flow in both directions

2. To restrict flow in one direction only

3. To maintain constant pressure

4. To enhance feed water quality

The correct answer is: To restrict flow in one direction only

The primary purpose of a check valve on a feed water line to a steam boiler is to restrict flow in one direction only. This device is critical for preventing backflow, which can occur if there is a drop in pressure or if the boiler system experiences a failure. By ensuring that water flows into the boiler while preventing it from flowing back into the feed water line, the check valve helps maintain the integrity and efficiency of the boiler system. This is particularly important in preventing contamination of the feed water, as reverse flow can introduce unwanted materials from the boiler into the feed system. Maintaining unidirectional flow through a check valve is crucial for the overall safety and functionality of boiler operations. It helps to protect the system from damage and ensures that the boiler has the necessary water supply for steam generation without the risk of reverse flow.