An attachment commonly placed on a bibcock valve or toilet or urinal flush valve.
A pressure vacuum breaker is an important component of irrigation systems. What a pressure vacuum breaker does is to provide protection against backflow or back siphoning of water. This irrigation component keeps non-potable water from inadvertently entering the water supply through outlets of the irrigation system. How To Maintain A Pressure Vacuum Breaker. Since the pressure vacuum breaker is such an important part of an irrigation system it is important to ensure it is working properly. How A Pressure Vacuum Breaker Works. A pressure vacuum breaker consists of a check device or valve and an air inlet, usually a chamber vented to the atmosphere. The pressure vacuum breaker is installed close to the water source in the water flow before it goes into the sprinkler valves. How To Maintain A Pressure Vacuum Breaker. Since the pressure vacuum breaker is such an important part of an irrigation system it is important to ensure it is working properly. A vacuum breaker is an attachment commonly placed on a bibcock valve or toilet or urinal flush valve, that prevents water from being siphoned backward into the public drinking water system. This prevents contamination should the public drinking water system's pressure drop. A vacuum breaker typically contains a plastic disc that is pressed forward by water supply pressure, and covers small vent holes. Should the supply pressure drop, the disc springs back opening the vent holes (which let in outside air), and preventing backflow of water A pressure vacuum breaker (PVB) is a type of backflow prevention device, used to keep non-potable (or contaminated) water from entering the water supply. A PVB is similar to an atmospheric vacuum breaker (AVB), except that the PVB contains a spring-loaded poppet. This makes it acceptable for applications that are high hazard or where valves are downstream.
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what is a vacuum breaker