What is the primary function of a pressure vacuum breaker?

The primary function of a pressure vacuum breaker is to prevent backflow due to back-siphonage. This device is designed to protect the potable water supply from contamination that can occur when there is a sudden change in pressure within the irrigation system. When water pressure drops, there is a risk that contaminants from non-potable sources could be drawn back into the clean water supply.

A pressure vacuum breaker achieves this by using an air inlet valve that opens to allow air into the system when the pressure drops, effectively breaking the vacuum that would otherwise allow backflow to occur. This ensures that water flows in the intended direction, safeguarding the water supply from pollutants and maintaining its quality.

Other functions associated with irrigation systems, such as filtering out impurities or maintaining constant water pressure, are not the main role of the pressure vacuum breaker. It is solely focused on preventing back-siphonage, making it an essential component in protecting potable water systems.