Specification Sheet

Page 2 of 2
Rated Flow (established by approval agencies)
Flow Characteristics
Zurn Industries, LLC | Wilkins
1747 Commerce Way, Paso Robles, CA U.S.A. 93446 Ph. 855-663-9876, Fax [phone]
In Canada | Zurn Industries Limited
7900 Goreway Drive, Unit 10, Brampton, Ontario L6T 5W6, 877-892-5216
www.zurn.com
12" MIN.
30" MAX.
DIRECTION OF FLOW
AIR GAP
DRAIN
0
3
6
9
12
15
5
10
15
20
FLOW RATES (GPM)
PRESSURE LOSS (PSIG)
69
PRESSURE LOSS (kpa)
FLOW RATES (l/s)
MODEL 975XL2 1/4", 3/8" & 1/2" (STANDARD & METRIC)
35
1/2" (15mm)
103
0.95
0.76
0.570.38
0.19
137
3/8" (9mm)
1/4" (6mm)
Typical Installation
Local codes shall govern installation requirements. To be installed
in accordance with the manufacturers’ instructions and the latest
edition of the Uniform Plumbing 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 sufficient
side clearance for testing and maintenance. The installation shall
be made so that no part of the unit can be submerged or where
relief valve discharge could cause damage.
Specications
The Reduced Pressure Principle Backflow Preventer shall be certified to NSF/ANSI 61 shall be ASSE® Listed 1013, rated to
180° F, and supplied with full port ball valves. The main body and access covers shall be low lead bronze (ASTM B 584), the
seat ring and all internal polymers shall be Noryl™ and the seat disc elastomers shall be silicone. The checks shall be oriented
at a 45° angle upward and accessible for maintenance without removing the relief valve or the entire device from the line. If in-
stalled indoors, the installation shall be supplied with an air gap and “Y” type strainer. The Reduced Pressure Principle Backflow
Preventer shall be a ZURN WILKINS Model 975XL2.
INDOOR INSTALLATION
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