This standard describes the reduced-pressure principle backflow prevention
assembly. The assembly shall be capable of withstanding a working water pressure of
at least 150 psi (1,034 kPa) without damage to working parts or impairment of
function and for operation on hot or cold water lines.
This...
Back to AWWA C511-07 Reduced-Pressure Principle Backflow Prevention Assembly (PDF)
This standard describes the reduced-pressure principle backflow prevention
assembly. The assembly shall be capable of withstanding a working water pressure of
at least 150 psi (1,034 kPa) without damage to working parts or impairment of
function and for operation on hot or cold water lines.
This standard describes hot and cold water reduced-pressure principle backflow
prevention assemblies. Assemblies shall be designed to operate, at a minimum, at a
temperature range of 33ºF to 140ºF (1ºC to 60ºC). Hot water assemblies shall be
designed to operate, at a minimum, in water at a temperature range of 33ºF to 180ºF
(1ºC to 82ºC).
A complete assembly consists of a mechanical, independently operating, hydraulically
dependent relief valve located between two independently operating, internally
loaded check valves that are located between two tightly closing resilient-seated shutoff
valves with four properly placed resilient-seated test cocks (see Sec. 4.3.1.3). Major revisions made to the standard in this revision
include the following:
AWWA standard materials statement has been added (Sec. III.A.2 and
Sec. 4.1);
synthetic coating of ferrous bodies has been removed. (Sec. 4.1.2);
the material callouts have been updated (Sec. 4.1.3);
the identification of nominal size of the assembly has been revised (4.2.1.1);
the requirements for structural capability and operational capability have
been revised (Sec. 4.2.2.1 and Sec. 4.2.2.2);
the sections on area of waterways, clearance of moving parts, facing rings
for poppet-type valves, facing rings for swing-type valves, bushings, diaphragms, and
air release have been removed (former Sec. 4.3.1.2 through 4.3.1.6, 4.3.1.10, and
4.3.1.11);
the requirements for control piping have been revised (Sec. 4.3.1.4);
the requirements for shutoff valves have been updated (Sec. 4.3.1.7); requirements for relief valve sensitivity have been added (Sec. 4.3.2.10);
requirements for operational cycle testing have been added (Sec. 4.3.2.11); and,
requirements for replacement parts have been added (Sec. 4.3.3).