Rev. K
Date: 8/24
Document No. BF-975XL
Product No. Model 975XL
Patent zurn.com/patents
Model 975XL
Reduced Pressure Principle Assembly
Page 1 of 2
Zurn Water, LLC | Wilkins
1747 Commerce Way, Paso Robles, CA U.S.A. 93446 Ph. 855-663-9876, Fax 805-238-5766
In Canada | Zurn Industries Limited
7900 Goreway Drive, Unit 10, Brampton, Ontario L6T 5W6, 877-892-5216
www.zurn.com
A
B
G
CD
F
E
975XL
W ILKINS
Z URN
OPTIONAL LEAD-FREE STRAINER
(MODEL SXL)
XL
WILKINS
Options
(Suxes can be combined)
- with full port QT ball valves (standard)
L - less ball valves, male pipe thread
U - with union ball valves (3/4" & 1")
FT - with integral male 45° flare SAE test fitting
S - with bronze "Y" type strainer
FDC - with fire hydrant connection; 2" only
SE - with street elbows (3/4" & 1")
Accessories
Air gap (Model AG)
Repair kits
Thermal expansion tank (Model XT)
Soft seated check valve (Model 40XL2)
Shock arrester (Model 1260XL)
QT-SET Quick Test Fitting Set
Application
Designed for installation on water lines to protect
against both backsiphonage and backpressure of
contaminated water into the potable water supply.
Assembly shall provide protection where a potential
health hazard exists. For non-potable applications only.
Standards Compliance
• ASSE® Listed 1013
• cUPC® Listed
• UL® Classified (less shut-o valves or with OS&Y valves
• C-UL® Classified
• CSA® Certified B64.4
• AWWA compliant C511
• Approved by the Foundation for Cross Connection
Control and Hydraulic Research at the University of
Southern California
• NYC MEA 425-89-M VOL 3
Materials
Main valve body Cast Bronze ASTM B 584
Access covers Cast Bronze ASTM B 584
Fasteners Stainless Steel, 300 Series
Elastomers Silicone
Buna Nitrile
Polymers Noryl™
Springs Stainless Steel, 300 series
Features
Sizes: 3/4", 1", 1-1/4", 1-1/2", 2"
Maximum working water pressure 175 PSI
Maximum working water temperature 180°F
Hydrostatic test pressure 350 PSI
End connections Threaded ANSI B1.20.1
Relief Valve discharge port:
3/4” - 1” - 0.63 sq. in.
1 1/4” - 2” - 1.19 sq. in.
Dimensions & Weights (do not include pkg.)
MODEL
975XL
SIZE
DIMENSIONS (approximate)
A
B
C D E F G
WITH
BALL
VALVES
in. mm in. mm in. mm in. mm in. mm in. mm in. mm in. mm lbs. kg
3/4 20 12 305 7 3/4 197 2 1/8 54 3 76 3 1/2 89 5 127 16 1/8 410 12 5.5
1 25 13 330 7 3/4 197 2 1/8 54 3 76 3 1/2 89 5 127 17 3/8 441 14 6.4
1 1/4 32 17 432 10 15/16 278 2 3/4 70 3 1/2 89 5 127 6 3/4 171 22 9/16 573 28 12.7
1 1/2 40 17 3/8 441 10 15/16 278 2 3/4 70 3 1/2 89 5 127 6 3/4 171 24 1/16 611 28 12.7
2 50 18 1/2 470 10 15/16 278 2 3/4 70 3 1/2 89 5 127 6 3/4 171 26 1/2 673 34 15.4
⃟
Rated Flow (established by approval agencies)
Flow Characteristics
Page 2 of 2
Zurn Water, LLC | Wilkins
1747 Commerce Way, Paso Robles, CA U.S.A. 93446 Ph. 855-663-9876, Fax 805-238-5766
In Canada | Zurn Industries Limited
7900 Goreway Drive, Unit 10, Brampton, Ontario L6T 5W6, 877-892-5216
www.zurn.com
Typical Installation
Local codes shall govern installation requirements. To
be installed in accordance with the manufacturers’ in-
structions and the latest edition of the Uniform Plumb-
ing Code. Unless otherwise specified, the assembly
shall be mounted at a minimum of 12” (305mm) and a
maximum of 30” (762mm) above adequate drains with
sucient side clearance for testing and maintenance.
The installation shall be made so that no part of the
unit can be submerged.
OUTDOOR INSTALLATION
INDOOR INSTALLATION
Specifications
The Reduced Pressure Principle Backflow Preventer shall be shall be ASSE® Listed 1013, rated to 180°F, and
supplied with full port ball valves. The main body and access covers shall be bronze (ASTM B 584), the seat
ring and all internal polymers shall be Noryl™ and the seat disc elastomers shall be silicone. The first and
second checks shall be accessible for maintenance without removing the relief valve or the entire device from
the line. If installed indoors, the installation shall be supplied with an air gap adapter. For use in non-potable
applications only. The Reduced Pressure Principle Backflow Preventer shall be a ZURN WILKINS Model 975XL.
Capacity thru Schedule 40 Pipe
Pipe size 5 ft/sec 7.5 ft/sec 10 ft/sec 15 ft/sec
1/8" 1 1 2 3
1/4" 2 2 3 5
3/8" 3 4 6 9
1/2" 5 7 9 14
3/4" 8 12 17 25
1" 13 20 27 40
1 1/4" 23 35 47 70
1 1/2" 32 48 63 95
2" 52 78 105 167
AIR GAP
FITTING
12" MIN.
30" MAX.
FLOOR DRAIN
DIRECTION OF FLOW
FLOOR
975XL
WILKINS
ZURN
PROTECTIVE
ENCLOSURE
OPTIONAL
WATER METER
INLET SHUT-OFF
AIR GAP
DRAIN
DIRECTION OF FLOW
OPTIONAL LEAD-FREE STRAINER
(MODEL SXL)
975XL
W ILKIN S
ZUR N
W ILKIN S
XL
12" MIN.
30" MAX.
0
20
40
60
80
5
10
15
20
0
50
100
150
200
250
5
10
15
20
FLOW RATES (GPM)
PRESSURE LOSS (PSIG)
69
PRESSURE LOSS (kPa)
FLOW RATES (l/s)
MODEL 975XL2 3/4", 1", 1 1/4", 1 1/2" & 2" (STANDARD & METRIC)
35
3/4" (20mm)
1" (25mm)
1 1/4" (32mm)
103
15.8
12.6
9.56.3
3.2
5.0
3.82.52
1.26
1 1/2”
(40mm)
137
2" (50mm)
(PROVIDED BY OTHERS)