Double Check Valve Assembly (DCVA)
- 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.
- The most common type of backflow device.
- Only one DCVA required to serve the whole system; control valves can be located downstream of the DCVA.
- A City Recognized backflow assembly tester when installed, annually or when moved, or repaired must test DCVAs.
- No chemicals or fertilizers may be introduced into an irrigation system containing DCVAs.
- A DCVA is effective against backpressure backflow and backsiphonage but should be used to isolate only nonhealth hazards.