Watts 774 - Manual

Job Name ____________________________________________ Contractor ____________________________________________
Job Location __________________________________________ Approval ______________________________________________
Engineer ______________________________________________ Contractor’s P.O. No. ___________________________________
Approval ______________________________________________ Representative ________________________________________
Series 774
Double Check Valve Assemblies
Sizes: 2 1 ⁄
2
" – 12" (65 – 300mm)
Series 774 Double Check Valve Assemblies are de signed to pre vent
the reverse flow of polluted water from en ter ing into the potable water
system. This se ries can be ap plied, where approved by the lo cal au-
thority having ju ris dic tion, on non-health hazard installations. Fea tures
short end-to-end dimensions, light weight stain less steel body, and the
lowest head loss available.
Features
• Torsion spring check valve provides low head loss
• Short lay length is ideally suited for retrofit installations
• Stainless steel body is half the weight of competitive designs
reducing installation and shipping cost
• Stainless steel construction provides long term corrosion protection
and maximum strength
• Single top access cover with two-bolt grooved style coupling
for ease of maintenance
• Thermoplastic and stainless steel check valves for
trouble-free operation
• No special tools required for servicing
• Compact construction allows for smaller vaults and enclosures
• May be installed in horizontal or vertical "flow up" position
Materials
All internal metal parts: 300 Series stainless steel
Main valve body: 300 Series stainless steel
Check assembly: Noryl ®
Flange dimension in accordance with AWWA Class D
Pressure - Temperature
Temperature Range: 33ºF – 110ºF (0.5ºC – 43ºC) continuous
Maximum Working Pressure: 175psi (12.1 bar)
Specifications
A Double Check Valve Assembly shall be in stalled at each not ed location
to prevent the un want ed reversal of pol lut ed water into the potable water
supply. The main valve body shall be manufactured from 300 series stain-
less steel to pro vide corrosion resistance. The check valves shall be of
ther mo plas tic construction with stainless steel hinge pins, cam arm, and
cam bearing. The check valves shall uti lize a sin gle torsion spring design
to minimize pressure drop through the as sem bly. The check valves shall
be modular and shall seal to the main valve body by the use of an O-ring.
There shall be no brass or bronze parts used within the check valve as-
sembly. The valve cover shall be held in place through the use of a single
grooved style two-bolt coupling. The main assembly shall consist of two
in de pen dent ly op er at ing torsion spring check as sem blies, two resilient
seat ed iso la tion valves, and four ball valve type test cocks. The as sem bly
shall be a Watts Series 774.
ES-774
Testcocks
Stainless Steel
Cover
Grooved
Coupling
Resilient
Disc
Replaceable
Seat
Captured Torsion
Spring
Laser Cut / Polished
Cam Arm
774 OSY
For Non-Health Hazard Applications
IMPORTANT: INQUIRE WITH GOVERNING AUTHORITIES
FOR LOCAL INSTALLATION REQUIREMENTS
Now Available
WattsBox Insulated Enclosures.
For more information, send for literature ES-WB.
Available Models
Suffix:
NRS -
non-rising stem resilient seat ed gate valves
OSY - UL/FM resilient seated outside stem & yoke gate valves
LF - without shutoff valves
S - cast iron strainer
**OSY FxG – Flanged inlet gate connection and grooved outlet
gate connection
**OSY GxF – Grooved inlet gate connection and flanged outlet
gate connection
**OSY GxG – Grooved inlet gate connection and grooved outlet
gate connection
Available with grooved NRS gate valves - consult factory**
Post indicator plate and operating nut available - consult factory**
**Consult factory for dimensions
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 wetted surface of this product contacted by consumable water con-
tains less than one quarter of one percent (0.25%) of lead by weight.
LEAD FREE
*