Backflow Prevention Practice Exam

What should be done if trapped air is detected in a double check valve assembly?

1. Replace the valve

2. Vent the assembly

3. Increase pressure

4. Perform a chemical flush

The correct answer is: Vent the assembly

When trapped air is detected in a double check valve assembly, venting the assembly is the appropriate action. This process involves releasing the trapped air to restore proper function and ensure that the assembly operates effectively in preventing backflow. Air trapped within the assembly can impede the flow of water, potentially leading to improper sealing of the valves, which can increase the risk of backflow and compromise the system's integrity. Trapped air can create pockets that disrupt the hydraulic seal required for the valve to function correctly. By venting the assembly, you're allowing the air to escape, which helps to maintain optimal pressure levels and ensures that the valve can properly seal when necessary. In contrast, replacing the valve may not be necessary if the issue can be resolved by simply venting it. Increasing pressure could exacerbate the issue of trapped air, and performing a chemical flush is typically unrelated to the immediate need for addressing air entrapment. Thus, venting the assembly emerges as the most effective solution for dealing with trapped air in a double check valve assembly.