Backflow Testing & Certification
We install, test, certify and submit the paperwork for Backflow preventers. There are several types of backflow preventers out there. We are going to help you understand about the three most common ones.
- Atmospheric Vacuum Breaker (AVB)
- Double Check (DC)
- Reduced Pressure Zone (RPZ)
The Atmospheric Vacuum Breaker is a non-testable unit and are good for back siphonage only for non-health hazard or health hazard conditionings. They must be installed downstream from any shut off valves and cannot be under any pressure. These are common on your outside hose connections.
The Double Check Valves are used in non-health hazard (pollutant) conditions only and are designed to protect against backflow pressure and back siphonage. They are basically a device with two check valves inline designed to prevent backflow. The DCV needs to be tested and certified every year to ensure it is working properly. There is paperwork filled out for the certifying of the valve, a copy must remain with the valve at all times and a copy submitted to the local water department.
The Reduced Pressure Zone (RPZ) is the best mechanical means of preventing backflow pressure and back siphonage. These are made for non-healthy hazard or high-hazard conditions and are designed to protect against back siphonage or back pressure. These assemblies are the most expensive backflow prevention devises but are the best way to protect against cross connections while in operational conditions. The RPZ assemblies may spit out water of relief port for a variety of reasons, so there must be a floor drain if being installed inside a building. Some of the reasons for spitting or flow from relief valve ports are if they detect backflow, inlet/outlet pressure fluctuations, dirt, or debris on first check valve or relief valve. The RPZ needs to be tested and certified every year to ensure it is working properly. There is paper worked filled out for the certifying of the valve, a copy must remain with the valve at all times and a copy submitted to the local water department.