Pressure vacuum breaker
Encyclopedia
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. Pressure vacuum breakers must be protected from freezing when installed outdoors. PVBs usually have test cocks, to which specially-calibrated gauges are attached, in order to ensure that they are functioning properly.
PVBs are manufactured by Watts
, Febco, Zurn and other manufacturers. Backflow prevention devices such as PVBs are regulated by the Uniform Plumbing Code
, but may also be required by government regulations.
Backflow prevention device
A backflow prevention assembly is used to protect water supplies from contamination or pollution.In water supply systems, water is normally maintained at a significant pressure to enable water to flow from the tap, shower etc...
, used to keep non-potable (or contaminated) water from entering the water supply. A PVB is similar to an atmospheric vacuum breaker
Atmospheric vacuum breaker
An Atmospheric Vacuum Breaker is a backflow prevention device used in plumbing to prevent backflow of non-potable liquids into the drinking water system. It is usually constructed of brass and resembles a 90-degree elbow with a hood on its top to allow air to enter the water system if a siphon...
(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. Pressure vacuum breakers must be protected from freezing when installed outdoors. PVBs usually have test cocks, to which specially-calibrated gauges are attached, in order to ensure that they are functioning properly.
PVBs are manufactured by Watts
Watts
-People:*Watts , the surname of several people*Watts S. Humphrey , American software engineer often called the father of software quality*Watts , a Canadian record producer-Fictional characters:*Watts family in EastEnders...
, Febco, Zurn and other manufacturers. Backflow prevention devices such as PVBs are regulated by the Uniform Plumbing Code
Uniform Plumbing Code
Designated as an American National Standard, the Uniform Plumbing Code is a model code developed by the International Association of Plumbing and Mechanical Officials to govern the installation and inspection of plumbing systems as a means of promoting the public's health, safety and welfare.The...
, but may also be required by government regulations.
See also
- Air gap
- Atmospheric vacuum breakerAtmospheric vacuum breakerAn Atmospheric Vacuum Breaker is a backflow prevention device used in plumbing to prevent backflow of non-potable liquids into the drinking water system. It is usually constructed of brass and resembles a 90-degree elbow with a hood on its top to allow air to enter the water system if a siphon...
- Chemigation valveChemigation valveA chemigation valve is an apparatus designed to protect water supplies from agricultural chemicals used during chemigation, the application of chemicals such as fertilizers and pesticides through irrigation water...
- Double check valveDouble check valveA double check valve or double check assembly is a backflow prevention device designed to protect water supplies from contamination. It is also a valve used in air brake systems on heavy trucks.Usage in Water Supply:...
- Hydrostatic loopHydrostatic loopA hydrostatic loop, though not often used in plumbing practice, is an arrangement of pipes formed into a vertical loop to prevent backflow of water within the plumbing potable water system. Since a siphon has a maximum height that it can work , a hydrostatic loop is built higher than 33 feet...
- Reduced Pressure Principle BFP