Watts LF757NDCDA - Manual

ES-LF757DCDA/LF757NDCDA
Series LF757DCDA,
LF757NDCDA
Double Check Detector Assemblies
Sizes: 2 1 /
2
" – 10"
Series LF757DCDA, LF757NDCDA 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 LF757DCDA, LF757NDCDA
may be installed under continuous pressure service and may
be subjected to backpressure and backsiphonage. Series
LF757DCDA, LF757NDCDA is used primarily on fire line sprin-
kler systems when it is necessary to monitor unauthorized
use of water.
Features
• Lead Free* construction
• Extremely compact design
• 70% lighter than traditional designs
• 304 (Schedule 40) stainless steel housing & sleeve
• Groove fittings allow integral pipeline adjustment
• Unique 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 Lead Free* Double Check Detector Assembly shall con-
sist 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 service-
able, without the use of special tools. The housing shall be
constructed of 304 Schedule 40 stainless steel pipe with groove
end connections. 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 gallon or cubic measurement, a double check backflow
assembly and required test cocks. Assembly shall be a Watts
Series LF757DCDA, LF757NDCDA.
LF757DCDAOSY
LF757DCDABFG
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.
For Non-Health Hazard Applications
LEAD FREE
*
Job Name ––––––––––––––––––––––––––––––––––––––––––– Contractor ––––––––––––––––––––––––––––––––––––––––––––
Job Location ––––––––––––––––––––––––––––––––––––––––– Approval –––––––––––––––––––––––––––––––––––––––––––––
Engineer ––––––––––––––––––––––––––––––––––––––––––––– Contractor’s P.O. No. ––––––––––––––––––––––––––––––––––
Approval ––––––––––––––––––––––––––––––––––––––––––––– Representative ––––––––––––––––––––––––––––––––––––––––
*The wetted surface of this product contacted by consumable
water contains less than 0.25% of lead by weight.
LF757NDCDAOSY