Watts 757NDCDA - Manual

For Non-Health Hazard Applications
ES-757DCDA/757NDCDA
Job Name ––––––––––––––––––––––––––––––––––––––––––– Contractor ––––––––––––––––––––––––––––––––––––––––––––
Job Location ––––––––––––––––––––––––––––––––––––––––– Approval –––––––––––––––––––––––––––––––––––––––––––––
Engineer ––––––––––––––––––––––––––––––––––––––––––––– Contractor’s P.O. No. ––––––––––––––––––––––––––––––––––
Approval ––––––––––––––––––––––––––––––––––––––––––––– Representative ––––––––––––––––––––––––––––––––––––––––
Series 757DCDA,
757NDCDA
Double Check Detector Assemblies
Sizes: 2 1 /
2
" – 10" (65 – 250 mm)
Series 757DCDA, 757NDCDA Double Check Detector
Assemblies are used to prevent backflow of non-health hazard
pollutants that are objectionable but not toxic, from entering
the potable water supply system. The 757DCDA, 757NDCDA
may be installed under continuous pressure service and may
be subjected to backpressure and backsiphonage. Series
757DCDA, 757NDCDA is used primarily on fire line sprinkler
systems when it is necessary to monitor unauthorized use of
water.
Features
• Extremely compact design
• 70% Lighter than traditional designs
• 304 (Schedule 40) stainless steel housing & sleeve
• Groove fittings allow integral pipeline adjustment
• Patented tri-link spring check provides lowest pressure loss
• Unmatched ease of serviceability
• Available with grooved butterfly valve shutoffs
• May be used for horizontal, vertical or N pattern installations
• Replaceable check disc rubber
Specifications
The Double Check Detector Assembly shall consist of two
independent tri-link check modules within a single housing,
sleeve access port, four test cocks and two drip tight shutoff
valves. Tri-link checks shall be removable and serviceable, with-
out the use of special tools. The housing shall be constructed
of 304 Schedule 40 stainless steel pipe with groove end con-
nections. Tri-link checks shall have reversible elastomer discs
and in operation shall produce drip tight closure against reverse
flow caused by backpressure or backsiphonage. The bypass
assembly shall consist of a meter, which registers in either gal-
lon or cubic measurement, a double check backflow assembly
and required test cocks. Assembly shall be a Watts Regulator
Company Series 757DCDA, 757NDCDA.
757DCDAOSY
757NDCDAOSY
757DCDABFG
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.