Product Overview
FEBCO product specifications in U.S. customary units and metric are approximate and are provided for reference only. For precise mea-
surements, please contact FEBCO. FEBCO reserves the right to change or modify product design, construction, specifications, or materials
without prior notice and without incurring any obligation to make such changes and modifications on FEBCO products previously or subse-
quently sold.
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The FEBCO Series LF825Y Reduced Pressure Zone Assemblies are used
to protect against high hazard (toxic) fluids in water services to industrial
plants, hospitals, morgues, mortuaries, and chemical plants. They are also
used in irrigation systems, boiler feed, water lines and other installations
requiring maximum protection. The LF825Y features Lead Free* construc-
tion to comply with Lead Free* installation requirements.
Features
• Ultimatemechanicalprotectionofpotablewater,againsthazardsof
cross-connection contamination.
• MeetsallspecificationsofAWWA,ASSE,CSAandapprovedbythe
Foundation for Cross-Connection Control and Hydraulic Research at the
UniversityofSouthernCalifornia.
• FlowcurvegeneratedbytheFoundationofCross-ConnectionControl
andHydraulicResearchattheUniversityofSouthernCalifornia.
• Modularreliefvalveforeaseofmaintenance.
• SimpleServiceprocedures.Allinternalpartsserviceableinline.
• Lowheadloss.
• Springloaded“Y”typecheckvalves.
• Internalreliefvalvepressuresensingpassages.
• Replaceableseatringsonallsizes.
• Endconnection–NPTANSI/ASMEB1.20.1
Specifications
The reduced pressure zone assembly shall consist of two independently
operating,springloaded,“Y”patterncheckvalvesandonehydraulically
dependent differential relief valve. The assembly shall automatically reduce
thepressureinthe“zone”betweenthecheckvalvestoatleast5psilower
than inlet pressure. Should the differential between the upstream and the
zone of the unit drop to 2psi, the differential relief valve shall open and main-
tain the proper differential.
Mainlinevalvebodyandcapsincludingreliefvalvebodyandcovershallbe
LeadFree*bronze.Checkvalvemovingmembershallbecenterstemguid-
ed. All hydraulic sensing passages shall be internally located within the main-
line and relief valve bodies and relief valve cover. Diaphragm to seat area
ratioshallbe10:1minimum.Reliefvalveshallhavearemovableseatring.
Checkvalveandreliefvalvecomponentsshallbeconstructedsotheymay
be serviced without removing the valve body from the line. All seat discs
shallbereversible.Shutoffvalvesandtestcocksshallbefullportedballvalves.
Theassemblyshallberatedto175psi(12.1bar)workingpressureandwater
temperaturerangefrom32°Fto140°F(0ºC-60ºC).The Lead Free* Reduced
Pressure Zone Assemblies shall comply with state codes and standards,
where applicable, requiring reduced lead content.
TheassemblyshallmeettherequirementsofASSEStandard1013;AWWA
StandardCodeC511;CSAStandardB64.4;andapprovedbytheFoundation
for Cross-Connection Control and Hydraulic Hydraulic Research at the
UniversityofSouthernCalifornia.
Operation
Inaflowconditionthecheckvalvesareopenwiththepressurebetween
thechecks,calledthezone,beingmaintainedatleast5.0psilowerthanthe
inlet pressure and the relief valve is maintained closed.
Should abnormal conditions arise under no flow or reversal of flow, the
differential relief valve will open and discharge to maintain the zone at least
2psi lower than the supply.
Whennormalflowresumes,thezone’sdifferentialpressurewillresume
and the relief valve will close.
Typical Installation
Reduced pressure zone assemblies should be installed with minimum
clearanceof12"(300mm)betweenreliefvalvedischargeportandflooror
grade. They must be installed where discharge will not be objectionable
and can be positively drained away. They should be installed where eas-
ily accessible for testing and maintenance and must be protected from
freezing.Thermalwaterexpansionand/orwaterhammerdownstreamof
thebackflowpreventercancauseexcessivepressure.Excessivepressure
situations should be eliminated to avoid possible damage to the system
and assembly.
Refer to local codes for specific installation requirements. Some codes
may prohibit vertical installation.
* The wetted surface of this product contacted by consumable water con-
tainslessthanonequarterofonepercent(0.25%)ofleadbyweight.
30" Max. (700mm)
12" Min. (300mm)
Flow
ES-F-LF825Y
S P E C I F I C A T I O N S H E E T
Series LF825Y
Lead Free* Reduced Pressure Zone Assemblies
Size:
3
⁄4" - 2" (20mm - 50mm)
LEAD FREE
*
LF825Y