Backflow Prevention Practice Exam

Which of the following represents a key indicator of a failed check valve?

1. Water pressure increase

2. Continuous backflow

3. Stable water temperature

4. Normal gauge reading

The correct answer is: Continuous backflow

A key indicator of a failed check valve is continuous backflow. Check valves are designed to allow fluid to flow in only one direction, preventing any reverse flow. When a check valve fails, it can no longer perform this function, resulting in backflow. This situation can pose significant risks, such as contamination of the potable water supply and system inefficiency. Continuous backflow signifies that the check valve is not sealing properly or has been compromised, leading to the undesirable condition of water flowing in the reverse direction. This is a critical failure, as it undermines the purpose of the backflow prevention system, which is to maintain the integrity of the water system by preventing reverse flow. The other options do not effectively indicate a failed check valve. For instance, an increase in water pressure, stable water temperature, or normal gauge reading may not directly correlate to the valve's performance and could be influenced by various factors unrelated to backflow prevention. These indicators may not provide the clear and direct evidence that continuous backflow does in identifying a failure in the system.