Specifications

35
Tech Support: 855-ONE-ZURN
www.zurn.com
OptionsTypical Installation
Model 975LXLMS FNPT x FNPT end connections
Model 975LXLMS Less shut-off valves
Model 975XLMSS Supplied with wye Strainer
Model 975XLMSU Union connections between ball valves and the
device
For Additional Information, reference WK-BPC catalog or visit
our web site.
Reduced Pressure Principle with Integral Relief Valve
Monitor Switch 975XLMS Series Pat. No. 5,425,393
Features Applications
• 3/4”, 1”, 1
1
/
4
”, 1
1
/
2
”, 2”
• Reduced pressure principle backflow preventer with patented integral
relief valve monitor switch
• When connected to a low voltage alarm circuit, the monitor switch
electrically supervises the relief valve in the closed position
• In the event of a backflow condition, the relief valve closes an electrical
circuit, signaling that a possible relief valve discharge may be occurring
• Weather-resistant housing and wire leads
• Switch contact rating 3A @ 24V
• Bronze body and cover construction
• Spring-loaded, center guided check valves
• Noryl
®
replaceable seats
• Entire unit serviceable in line
• Temperature range 33°F – 180°F
• Maximum pressure 175 psi
• UL
®
recognized switch – supplied with normally open contacts
• Switch is factory installed and ready for immediate installation to appropriate
electrical circuit
• With BSP threaded connections
• Self-contained monitor switch is also available as a kit to retrofit existing
975XL installations.
• ASSE
®
Listed 1013, IAPMO
®
Listed, AWWA Compliant, CSA
®
Certified
• Approved by the Foundation for Cross-Connection Control and
Hydraulic Research at the University of Southern California
Reduced pressure principle assemblies are designed to discharge water. Relief valve discharge can
result in severe property damage should the discharge go undetected. The Wilkins 975XLMS can
alleviate the potential damage. The relief valve is equipped with a monitor switch that when at-
tached to the appropriate alarm, will notify the proper authorities that the relief valve is discharging.
Hence the discharge can be corrected before damage occurs. While still providing the superior
protection of the 975XL the 975XLMS can also be used in conjunction with the ZW106 and EST
allowing for a total shut-off of the water during relief valve discharge.
 Air gap (Model AG)
 Thermal expansion tank (Model XT)
 Soft seated check valve (Model 40XL)
 Water hammer arrestor (Model 1250)
Local codes shall govern installation requirements. To be installed in accordance with the manufacturer’s 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.
 Quick test set (QT-SET)
 Test cock lock (Model TCL24)
 Ball valve monitor switch (Model BVMS)
Accessories
INDOOR INSTALLATIONOUTDOOR INSTALLATION
12" MIN.
30" MAX.
TO LOW VOLTAGE ELECTRICAL
CONTACT PANEL WITH ALARM,
LIGHT, HORN, ETC.
PROTECTIVE
ENCLOSURE
MODEL 975XLMS
12" MIN.
30" MAX.
DIRECTION OF FLOW
TO LOW VOLTAGE ELECTRICAL
CONTACT PANEL WITH ALARM,
HORN, LIGHT, ETC.
MODEL 975XLMS
Backflow Preventers