Backflow preventers are mechanical plumbing devices installed in a plumbing system to prevent water from flowing backward in the system. A properly installed, tested and maintained backflow preventer at the service entrance to a building or property can reliably prevent the backflow of water of an unknown quality from flowing back into the community water system.
Backflow Preventer Maintenance
Mechanical backflow assemblies and preventers have internal check valves, seals, springs and moving parts that wear over time. These assemblies and preventers have to be tested annually to ensure that they are working properly.