Water leaking from a properly installed atmospheric vacuum breaker may be caused by what issue?

Water leaking from a properly installed atmospheric vacuum breaker can indeed be caused by a damaged or corroded guide. The function of the guide in an atmospheric vacuum breaker is crucial, as it helps ensure that the moving parts within the device operate smoothly. If the guide is compromised due to damage or corrosion, it may not allow the internal mechanism to function properly. This malfunction can lead to water escaping or leaking from the device, even if the vacuum breaker itself is installed correctly.

In contrast, while improper installation and excessive pressure might also lead to operational issues in some scenarios, they typically wouldn't result in leaking from an otherwise functioning unit. Clogged outlets could cause back pressure or additional operational problems, but again, they do not typically cause leakage under normal conditions where the device is installed and functioning as intended. Thus, understanding the role of the guide and its condition is key to diagnosing potential leaks in atmospheric vacuum breakers.