1)Why do I need my "Backflow Prevention Assembly" tested annually? a. Backflow Prevention Assemblies and Devices break or wear out, just like the parts of a car. Backflow is the hydraulic condition that can cause an RP to stop working in the described normal flow pattern. Backflow can happen by either backpressure andor backsiphonage (b). Backpressure is a condition where a greater pressure is generated on the downstream than the upstream side of the assembly. This condition can happen for many reasons, pumps, thermal expansion, etc. By having your Backflow Prevention Assembly tested annually, you will help to ensure that the drinking water supplied to you and your neighbors home remains safe. Pure drinking water is our greatest resource. We have Certified Technicians on our staff that have attended rigorous training, and are able to test your Backflow Prevention Assembly.
2) Why have I never had to test my Backflow before? a. When your Backflow was installed it was tested prior to plumbing inspection, but because of the volume of Backflow preventers being installed and the large number of existing Backflow preventers in various cities it is not easy for municipalities to keep you informed of when your Backflow is due to be tested. However, due to increased awareness of the importance of protecting our water many cities are taking better steps to inform people when their annual test is due.
3) What is a Backflow preventer? a. A Backflow preventer is a mechanism to prevent Backflow. The basic means of preventing Backflow is an air gap, which provides a barrier to Backflow. The basic mechanism for preventing Backflow is a mechanical Backflow preventer, which provides a physical barrier to Backflow. The principal types of mechanical Backflow preventers are the reduced-pressure principle assembly, the pressure vacuum breaker assembly, and the double check valve assembly. A secondary type of mechanical Backflow preventer is the residential dual check valve.
4) What is a reduced principle (RP) assembly? a. An RP is a mechanical Backflow preventer that consists of two independently acting,spring-loaded check valves with a hydraulically operating, mechanically independent, spring-loaded pressure differential relief valve between the check valves and below the first check valve. It includes shutoff valves at each end of the assembly and is equipped with test cocks. An RP is effective against back pressure and backsiphonage and may be used to isolate health or non-health hazards.
5)What is Backsiphonage? a. Backsiphonage is a condition that causes a sub-atmospheric pressure to be applied to the upstream side of the assembly. Backsiphonage can happen for several reasons; one of the more common is excessive water demand in the distribution system.
6) What is an air gap? a. An air gap is a vertical, physical separation between the end of a water supply outlet and the flood-level rim of a receiving vessel.This separation must be at least twice the diameter of the water supply outlet and never less than one inch. An air gap is considered the maximum protection available against back pressure Backflow or backsiphonage, but is not always practical and can be easily bypassed
7) What is a double check valve assembly? a. A DCVA is a mechanical Backflow preventer that consists of two independently acting, spring-loaded check valves. It includes shutoff valves at each end of the assembly and is equipped with test cocks. A DC is effective against back pressure Backflow and backsiphonage but should be used to isolate only non- health hazards.