Backflow Prevention Practice Exam

What indicates that the air-inlet valve is working properly?

1. Air enters freely when needed

2. Regular pressure drops

3. Constant flow from test cock 2

4. Minimal pressure variations

The correct answer is: Air enters freely when needed

The air-inlet valve's proper functioning is indicated when air enters freely when needed. This is crucial because the air-inlet valve serves to maintain air pressure within a backflow prevention assembly, particularly during a backflow condition or when the water pressure drops within the system. When the valve operates correctly, it allows air to enter the system to equalize pressure, preventing a vacuum that could lead to a backflow situation. Free flow of air into the system demonstrates that the valve is not obstructed and is responding appropriately to changes in system pressure. In contrast, issues like regular pressure drops or constant flow from test cock 2 would suggest potential problems with the overall system or its components rather than specifically indicating the proper function of the air-inlet valve. Similarly, minimal pressure variations may not necessarily confirm the valve's proper operation; pressure stability can be influenced by various factors within the water supply system. Therefore, the ability for air to enter freely when required is the definitive indication of the air-inlet valve’s functionality.