Specification Sheet

ES-957RPDA_957NRPDA_957ZRPDA
Series 957RPDA,
957NRPDA,
957ZRPDA
Reduced Pressure Detector
Assemblies
Sizes: 2
1
⁄2" – 10"
Series 957RPDA, 957NRPDA, 957ZRPDA Reduced Pressure
Detector Assemblies provide protection to the potable water
system from contamination in accordance with national plumb-
ing codes. The 957RPDA, 957NRPDA, 957ZRPDA are normally
used in health hazard applications to protect against back-
siphonage and backpressure. The Watts 957RPDA, 957NRPDA,
957ZRPDA are used to monitor unauthorized use of water from
the fire protection system.
Features
• Extremely compact design
• 70% lighter than traditional designs
• 304 (Schedule 40) stainless steel housing & sleeve
• Groove fittings allow integral pipeline adjustment
• Patented torsion spring check provides lowest pressure loss
• Unmatched ease of serviceability
• Replaceable check disc rubber
• Available with grooved butterfly valve shutoffs
• Bottom mounted cast stainless steel relief valve
• Metered bypass to detect leakage or theft of water from the
fire sprinkler system
957NRPDAOSY
Specifications
The Reduced Pressure Detector Assembly shall consist of two
independent torsion spring check modules, a differential pres-
sure relief valve located between and below the two modules,
two drip tight shutoff valves, and required torsion spring check
modules and relief valve shall be contained within a sleeve
accessible single housing constructed from 304 (Sch 40) stain-
less steel pipe with groove end connections. Torsion spring
checks shall have reversible elastomer discs and in opera-
tion produce drip tight closure against reverse flow caused by
backpressure or backsiphonage. The bypass line shall include
a meter, small diameter reduced pressure zone assembly and
isolation valves. Assembly shall be Watts Series 957RPDA,
957NRPDA, 957ZRPDA.
It is illegal to use this product in any plumbing system providing water
for human consumption, such as drinking or dishwashing, in the United
States. Before installing standard material product, consult your local
water authority, building and plumbing codes.
WARNING
!
Watts product specifications in U.S. customary units and metric are approximate and are provided for reference only. For precise measurements,
please contact Watts Technical Service. Watts reserves the right to change or modify product design, construction, specifications, or materials with-
out prior notice and without incurring any obligation to make such changes and modifications on Watts products previously or subsequently sold.
The information contained herein is not intended to replace the
full product installation and safety information available or the
experience of a trained product installer. You are required to
thoroughly read all installation instructions and product safety
information before beginning the installation of this product.
NOTICE
Job Name
–––––––––––––––––––––––––––––––––––––––––––
Contractor
––––––––––––––––––––––––––––––––––––––––––––
Job Location
–––––––––––––––––––––––––––––––––––––––––
Approval
–––––––––––––––––––––––––––––––––––––––––––––
Engineer
–––––––––––––––––––––––––––––––––––––––––––––
Contractor’s P.O. No.
––––––––––––––––––––––––––––––––––
Approval
–––––––––––––––––––––––––––––––––––––––––––––
Representative
––––––––––––––––––––––––––––––––––––––––