Zurn Wilkins ZW207 Manual

NOTE: Flushing of all pipe lines is to be performed to remove
all debris prior to installing valve.
1. For making adjustments and servicing allow for adequate space
around the valve before installing valve.
2. When installing a ZW207, gate valves installed prior to the
ZW209 and after the ZW207 are recommended for maintenance
allowing for isolation of valves.
3. Positionthevalveinlinematchingthedirectionofowasindi-
catedonthevalvemodeltagwiththeproperdirectionofowinthe
system.Connectadrainlinetothedischargeorice(greentting)
in the valve pilotry, as water will discharge when the valve closes.
Note: Do not remove the discharge orice tting. The ZW207
will not operate correctly without the tting. The end connec-
tionofthedischargettingisastandard3/8",45degree,are.
Onceattachedtoline,doublecheckallfasteners/boltsinthepilot
system and on main valve are tight and there is no damage prior
to pressurizing system.
NOTE: Pressure in some applications can be very high so be
thorough in checking and inspecting for proper installation
and makeup.
4.ZurnWilkinsvalvesaredesignedtooperateinboththevertical
and horizontal positions. However, it is recommended that ZW207
6” and larger, be installed in the horizontal position. The horizontal
positioning of the larger valves avoids premature wear due to the
mass of plunger assemblies as well as allows for greater acces-
sibility during annual inspections, and maintenance.
ZW207 SCHEMATIC
STANDARD COMPONENTS
1 Main Valve
2850XLIsolationValve
3SXL"Wye"TypeStrainer
4PressureGauge
5RestrictionFitting
6PV-RLFPressureReliefValve
 Installation Troubleshooting  Maintenance Instructions
Model ZW207 LEAD-FREE*
Excess Pressure Shutdown Valve
GlobeandAnglePatternBodies
11/4",11/2",2",2-1/2",3",4",6",8",10",12",14"&16"
*Containsaweightedaverageleadcontentlessthan0.25%forwettedsurfaces
OPTIONAL FEATURES
C40XL2HydraulicCheckw/
IsolationValve
ZZPIValvePositionIndicator
START-UP
CAUTION: To prevent personnel injury and damage to equip-
ment check that downstream venting is adequate prior to start-up
and test procedures. All adjustments under pressure should
be made slowly while under owing conditions.
Ifthemainvalveclosestoofastitmaycausesurginginupstream
piping.
1. Start-up and set the outlet pressure for the ZW209 before the
ZW207.
Note: Close the inlet isolation ball valve on the ZW207 pi-
lotry so the valve will open freely during ZW209 start-up.
2.TheZW207shouldbepressurizedandlledwithwaterfrom
the ZW209 Start-Up procedure, but the ZW207 pilotry will need
tobelled.Priortopressurizingthevalveassemblyitisalso
recommendedthataZPIvalvepositionindicatorbeinstalledto
aid in verifying proper valve movement.
3.Tollthevalvecoverandpilotrysystem,openisolationvalves
(2)inthepilotsystemoftheZW207(seeZW207schematic)and
back the adjustment screw out all the way on the pilot valve so
thecovercanstartllingwithwater.Note: Water will discharge
out of the orice at this time unless the inlet pressure is too
low. Increase the inlet pressure until water starts to discharge
from the orice. Atthistimeitisnecessarytobleedthecover.
Openthetopplugonthecoverandtopttingsofthepilotry.
Open the inlet shut off valves enough so you can see water and
air coming out of the cover and pilotry. Wait until only water is
comingoutthentightenttingsandplugs.Itmaybenecessaryto
bleedsystemmorethanonce.Afterremovalofairinthesystem
tightenallloosettings.NOTE: If valve is installed vertically, it
will be necessary to loosen some upper cover bolts until you
have vented all the air from the cover chamber.
4.TurntheZW207pilot(reliefpilot)adjustmentscrewclockwise
until the pilot spring is compressed completely.
5.Atthispointwiththeupstreamshutoffvalveopen,slowly
open the downstream shut off valve if not already open. Flow
will begin to occur and eventually stabilize.
6.Nextitisadvisabletoowwaterthroughthevalvetoensure
allairhasescapedfromsystem.Withwaterowingthroughthe
valve,settheZW209pressurereducingpilot10to15psihigher
than the desired pressure reducing set pressure so the ZW207
pilot can be set. To adjust the pressure reducing pilot, loosen jam
nutonadjustmentscrewandeitherturnadjustmentscrewin(to
increaseoutletpressure)orout(todecreaseoutletpressure).
7.NowsettheZW207pilot.Withwaterowingthroughthe
main valve, start to slowly turn the pilot adjustment screw
counterclockwiseuntiltheZW207startstoclose(downstream
pressurewillsignicantlydecrease).AtthispointtheZW207is
set at the current downstream pressure. Tighten the jam nut on
the ZW207 pilot valve.
Installation / Start-up
ZURN WILKINS
1747 Commerce Way, Paso Robles, CA 93446 Phone:[phone] Fax:[phone]
www.zurn.com
®
®
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BODY FLOWS BACKWARD
!WARNING:CancerandReproductiveHarm-www.P65Warnings.ca.gov
!ADVERTENCIA:Cáncerydañoreproductivo-www.P65Warnings.ca.gov
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PROBLEM POSSIBLE CAUSES CORRECTIVE ACTION
1.Lowdownstreampressure 1.NopressureatvalveInlet 1.CheckInletpressure
(MainValvefailstoopen) 2. Main valve diaphragm assembly 2. Disassemble, clean, and polish stem, replace defective
inoperative parts
3.ReliefPilotisnotclosing 3. See Pilot Troubleshooting Problem #2
4.Dischargeoriceordrainlineclogged 4.Disassembleandclean
2. High downstream pressure 1. Foreign matter between disc and 1. Disassemble the main valve, remove debris, clean parts,
(MainValvefailstoclose) seat or worn disc and replaced defective parts
2. Scale on stem or diaphragm ruptured 2. Clean parts, and replace defective parts
3."Wye"Strainerplugged 3.Remove,clean,and/orreplace
4.38-850XL(ballvalves)closed 4.Openballvalves
5.ReliefPilotremainsclosed 5.SeePilotTroubleshootingProblem#1
When performing troubleshooting and diagnosis checks it is recommended that the following steps be performed in sequential order
for best results.
Troubleshooting
TABLE 2. MAIN VALVE TROUBLESHOOTING
2ZURN WILKINS
1747 Commerce Way, Paso Robles, CA 93446 Phone:[phone] Fax:[phone]
www.zurn.com
®
ThefollowingtroubleshootinginformationinTables1and2dealsstrictlywiththeZW207valveandpilotsystems.Itisrecommend-
edtoverifythatthepilotsystemisproperlyfunctioningbeforetroubleshootingthemainvalve.Alltroubleshootingcanbeperformed
withoutremovingthecover.ItisalsorecommendedtopermanentlyinstallamodelZPIvalvepositionindicator.
PROBLEM POSSIBLE CAUSES CORRECTIVE ACTION
1. Downstream pressure going 1. Over compressed spring 1.Loosenadjustingscrew/Repeatstart-upprocedure
high/Controlvalvenotclosing 2. Small sensing port on inlet side 2. Disassemble and clean
quickly of pilot body clogged
3. Closed isolation ball valve 3. Open isolation ball valve
4.Worndiaphragmorstemo-rings 4.Disassembleandreplacediaphragmoro-rings
2.Lowdownstreampressure/ 1.Insufcientspringcompression 1.Tightenadjustingscrew/Repeatstart-upprocedure
Control valve not opening 2. Damaged spring 2. Disassemble and replace parts as necessary
3. Worn seat seal or seat 3. Disassemble and replace seat seal or seat
4.Obstructiononseat 4.Disassembleandremoveobstruction
5.Obstructionarounddiaphragm 5.Disassembleandremoveobstruction
6. Worn seat o-ring 6. Disassemble and replace as needed
TABLE 1. PRESSURE RELIEF PILOT SYSTEM TROUBLESHOOTING
8.Lowerthedownstreampressuretothedesiredsettingby
adjusting the pressure reducing pilot on the ZW209 back to the
desired outlet pressure. Once pilot is set, tighten the jam nut.
Note: Water will continuously discharge from the dis-
charge orice of the ZW207 when it is closed. Water will
stop discharging once the pressure reducing valve on the
ZW209 is adjusted to the desired set pressure.
9. To verify proper operation of ZW207 quickly close and open
downstream shut off valve several times to ensure downstream
pressure does not rise above the ZW207 set pressure.

Troubleshooting
PILOT SYSTEM FUNCTION CHECK
CAUTION: To prevent personnel injury and damage to
equipment check that downstream venting is adequate
prior to start-up and test procedures.
PILOT VALVE CHECK
1. With all isolation valves open on the ZW207 and with water
owingthroughthemainvalveturnthepilot(PV-RLF)adjust-
ment screw clockwise all the way in.
2.Whileowing,checkthedrainlinefromthepilotryofthe
ZW207.Acontinuousstreamofwatershouldnotdischarge
outofthedischargetting(brassttingcolorcodedingreen).
Asmallamountofwatermaydischargeatrstwhilethevalve
openscompletely.Ifwatercontinuouslydischargeseitherthe
pilot valve it is not sealing properly or there is a leak through
the diaphragm assembly of the main valve. To check, close
thecoverisolationvalve.Ifwaterstilldischargescontinuously
it is recommended that the pilot valve be disassembled and
inspected.Ifwaterstoppeddischarging,thenwaterisleaking
throughthediaphragmassemblyofthemainvalve.Itisrecom-
mended the main valve be disassembled and inspected.
3.Withwaterowingthroughthemainvalveturnthepilot
(PV-RLF)adjustmentscrewcounterclockwiseallthewayout.
Verify inlet pressure is higher than the low pressure range
speciedonthepilot.Themainvalveshouldclosenowand
waterwilldischargefromthepilotry.Ifinstalled,verifythevalve
positionindicator(modelZPI)isclosed.Ifwaterisnotdischarg-
ing from the pilotry then either the inlet pressure is too low or
the pilot valve isn’t opening properly. Verify inlet pressure is
higherthanthelowpressurerangespeciedonthepilotagain,
then disassemble and inspect the pilot if water still is not dis-
charging from the pilotry.
4.Ifthepilotvalveisoperatingcorrectlyandthereiscontinu-
ousowfromtheoutletofthemainvalve,themainvalveis
notsealingproperly.Itisrecommendedthatthemainvalvebe
disassembledandinspected(Referto“Disassembly”section).
5.Ifnothingiswrongthenopenallisolationvalvesandgo
through start-up procedure to set valve.
DIAGNOSIS CHECKS
CAUTION: Do not service valve while under pressure.
When performing diagnosis checks on the ZW207 when
the valve is fully open, high ow rates and high down-
stream pressures can occur.
DIAPHRAGM CHECK
1. Slowly close upstream shut off valve and relieve all pressure
downstream.
2. With all pressure relieved in the main valve, close both inlet
and outlet isolation valves and remove side plug on cover and
leave off.
3. Then open upstream shut off valve partially, allowing water
toowthroughthevalve.Whileowingwatermonitortheopen-
ingonthecover.Ifuidbeginstoowoutoftheopenholein
the cover, then there is most likely damage to the diaphragm
oruidisleakingpastthediaphragmassemblyduetoloose
assembly.Itisrecommendedthatthevalvecoverberemoved
toinvestigatetheleakage(Toremovecoversee“Maintenance”
sectionforprocedures).Ifnowaterowsoutofcoverthenthe
diaphragm is good and you may proceed to the diaphragm
movement check.
DIAPHRAGM MOVEMENT CHECK
1. The diaphragm movement check can be determined during
the diaphragm check or it can also be performed with the use of
avalvepositionindicatormodelZPI.
2.Replacecoverplugandopenpilotballvalvesoninletandcover.
3.Closingtheoutletisolationballvalveswilldirecttheowto
the cover causing it to close. NOTE: Slow or delayed closing
of main valve is normal and is due to the time requirements
to ll, pressurize cover, and stretch the diaphragm into the
closed position. This normal delay is not mechanical bind-
ing of the valve assembly.
4.Usingthevalvepositionindicator,makenoteoftheclosed
position on the indicator. Compare distance of the open mark to
the close mark and compare to Table 3.
5.Verifythatthemainvalveisclosed,byopeningadown-
streamsource(nottheoutletisolationballvalveonthemain
body).Ifwatercontinuouslyows,thenthemainvalveisnot
sealing properly. Double check the valve movement matches
the values in Table 3 and refer to the disassembly procedures
section if it does not. This is an indication that the main valve is
not sealing due to an obstruction between the seat and the seal
oradamagedseal.Ifwaterdoesstopowingandthemeasured
valve movement does not match Table 3, then there is possible
damageunderthecover.Removecovertoidentifyobstruction
and replace parts as necessary.
3
ZURN WILKINS
1747 Commerce Way, Paso Robles, CA 93446 Phone:[phone] Fax:[phone]
www.zurn.com
®
TABLE 3. VALVE STEM TRAVEL
VALVESIZE
(in)
VALVESIZE
(mm)
STEMTRAVEL
(in)
STEMTRAVEL
(mm)
1-1/4"-1-1/2" 38 0.4 10.2
2" 50 0.7 18.0
2-1/2" 65 0.8 21.3
3" 80 0.9 23.4
4" 100 1.1 28.8
6" 150 1.7 43.4
8" 200 2.4 59.7
10" 250 2.8 71.1
12" 300 3.4 86.4
14" 350 3.8 96.5
16" 400 4.3 109.2

6.Forsmallervalves(6”andbelow)diaphragmcheckscanbe
performed by hand with the use of a valve stem tool. The valve
stemtoolcanbemadeusingTable4tocreatea“T”barhandle
withtheappropriatethreadsontheoppositeendofthe“T”handle.
TABLE 4. VALVE STEM THREAD SIZE
7. To perform the diaphragm check using the vale stem tool,
rstremoveallpressureinthesystemandventthecover.
Then remove the center plug on the cover and insert tool into
the top of the stem threads. Once the tool is inserted, the
valve can be lifted up and the valve movement can be mea-
sured by creating marks on the tool in the opened and closed
positions. The distance between marks is the valve stem
travel.Replaceorrepairanypartsasnecessary.
SEAL CHECK
1. To check the seal of the valve disc, an additional pressure
gauge will be needed downstream of main valve.
2.Withthevalveowing,slowly,closepilotoutletballvalves
to apply pressure to cover and allow to close.
3. Open downstream source and monitor the pressure on the
inlet and installed outlet gauge, for one min. The pressure on
theoutletsideshouldremainzero.Ifthepressurematchesinlet
pressure or increases, the main valve is leaking or the outlet
ball valve on the pilot system is allowing pressure to creep by.
Either way it is recommended that the valve be disassembled
andinspected(referto“Disassembly”section).
Troubleshooting
Maintenance Instructions
PREVENTATIVE MAINTENANCE
The Zurn Wilkins ZW200 models require minimal maintenance.
However, it is highly recommended to schedule annual inspec-
tions and to have a repair kit on hand before work begins.
DISASSEMBLY
Warning: Because of the ability to perform inspections and
maintenance without removal from the system, it is very
important that all shut off valves be closed and all pressure
relieved in the valve before beginning disassembly. Failure
to do so can result in personnel injury or equipment damage.
1. Verify that all pressure sources are closed up and down-
stream of valve.
2.Removepressureinpilotsystembylooseningthetubet-
tings to the valve body and cover. When all pressure has been
vented, continue to disassemble the pilot control valve and
cover tubing. NOTE: Taking a picture before tear down can help
with re-assembly of pilot system.
3. Next remove the cover by loosening and removing the
coverbolts.Ifthecoverdoesnotcomeoffeasilyitmaybenec-
essary to loosen the cover using a brass chisel and rubber mal-
let.Applythechiselunderthecoverpointingupwardawayfrom
valve body and tap bottom of cover with the chisel and mallet to
loosen the cover. Once the cover is loose, pull cover straight up
to avoid damaging the stem and stem bearing in the cover. On
largervalves8”andup,eyeboltsandahoistarerecommended
due to the weight of these larger covers.
4.Withthecoverremovedthediaphragmassemblycanbe
removed. To avoid damaging the seat bushing, grab the stem
andliftstraightup.Forlargervalves8”andupitisrecommended
that an eye bolt with the proper stem threads be used with a
hoisttolifttheassemblyoutofthevalve(seeTable4forap-
propriatestemthreads).
5.Nextitisrecommendedthatthediaphragmassemblybe
placed in a vise with the bottom hex nut secured. Once secured
remove the spring and stem nut. While removing the nut inspect
the stem threads. Clean stem with a wire brush if mineral de-
posits or corrosion are present.
6.Afterinspectingthestemandremovingthenutthediaphragm
assemblycanbedismantled.Ifthevalvehasnotbeenserviced
in a while it is possible that the assembly will require the use of a
rubbermalletorprybarstodismantletheassembly.Ifthisisthe
case gently tap or pry the components until the components are
free to move. When disassembling be sure to clean, inspect, and
saveallcomponents.Replaceanydamagedcomponentsas
necessary.
7. The last component to inspect is the seat which is in the body
of the main valve. During inspection of the seat, clean and polish
asnecessarywithnegritwet/drysandpaper(400gritorhigher).
Typically, if after cleaning there is no visual damage or excessive
weartheseatshouldnotrequireremoval.Ifdamageispresent
or the seat is excessively worn the seat should be replaced.
8.Toremovetheseat,onvalves6”andsmallertheseatis
threaded into the body and will require a seat removal tool. Care
should be taken when removing the seat to avoid damaging.
On8”andlargervalves,theseatisheldinplacewithathead
hex screws. For larger valves a seat puller may be required to
remove the seat from the body.
INSPECTION OF COMPONENTS
Cleaningofcomponentsisrequiredforproperinspection.Lime
deposits are common in systems that use water. To remove
deposits,negritwet/drysandpaper(400gritorhigher)canbe
used.Ifdepositscannotberemoved,offtheshelflimedeposit
remover can be used. Prepare a solution following the lime
depositremoverinstructionsandsoakcomponents(excluding
rubbercomponents)untillimedepositsareremoved.
CAUTION: When handling chemicals (acids) be sure to use
proper safety equipment (gloves and eye protection) and
practices. After soaking components, be sure to thorough-
ly rinse all components before handling and re-assembling
valve.
Once all valve components have been cleaned, inspect each
componentlookingfordamage,abnormalwear&corrosion,
andreplaceallcomponentsthatlookquestionable.Replaceall
rubber components including the diaphragm, o-rings and disc
eachtimethevaleisservicedorinspected(rubbercomponents
are standard in ZW200 repair kits.
4ZURN WILKINS
1747 Commerce Way, Paso Robles, CA 93446 Phone:[phone] Fax:[phone]
www.zurn.com
®
VALVESIZE(in) THREADSIZEUNFINTERNAL
1-1/4"-1-1/2" 10-32
2" 10 - 32
2-1/2" 10 - 32
3" 1/4-20
4" 1/4-20
6" 1/4-20
8" 3/8-16
10" 3/8-16
12" 3/8-16
14" 3/8-16
16" 3/8-16

5
ZURN WILKINS
1747 Commerce Way, Paso Robles, CA 93446 Phone:[phone] Fax:[phone]
www.zurn.com
®
Maintenance Instructions
REASSEMBLY
1.Firstreinstallseatintobody.Besuretouselubearound
seat o-ring before tightening. Tighten seat according to torque
valuesinTable5usingseattool.
2. Next place valve stem in a vise clamping on the hex portion
of the stem. Then assemble the diaphragm assembly as shown
in Figure to the right. When assembling be sure that the dia-
phragmiscenteredontheraisedstepofthediscretainer.Itis
also recommended to apply lube to stem threads and o-rings
before tightening. Then tighten the stem nut according to Table
5fortorquevalues.
3.Lowerdiaphragmassemblycarefullyintotheseatbushing
Becarefulnottodamagetheseatorstemwhileinstallingas-
sembly.Rotatetheassemblyasneededuntiltheboltholeson
the diaphragm line up with the body bolt holes.
4.Placelowerspringdisconthediaphragmdiscandplace
spring on top of the assembly. Then install cover, aligning
the bolt holes and insuring that the cover is not pinching the
diaphragm between the bolt holes. Position cover so plug holes
are in original position.
5.Installcoverboltsandtighteninastarpatterntothetorque
valuesinTable5.
6.Beforeinstallingcentercoverplugmanuallycheckthat
assembly has full operating travel before installing the pilot
assembly(referto“DiaphragmMovement”inthediagnosis
checkssection).
7.Oncefulloperationrangeofthemainvalveisveried,
begin reinstalling pilot system.
8.Afterinstallingpilotsystemdoublecheckthatallplugs,
bolts,andttingsaresealedandtightbeforeapplyingpressure.
9. Slowly open upstream isolation valve to pressurize the
system and check for any leaks.
10.Stopleaksasneededandproceedto“Start-Up”and“Di-
agnosis Check” sections for returning valve to proper system
operations.
TABLE 5. VALVE TORQUE SETTINGS
COVER CENTER PLUG
COVER BOLTS
COVER NUTS (8" AND LARGER)
COVER PLUG
COVER
COVER BEARING (STEM GUIDE)
UPPER SPRING DISC (4" AND LARGER) * †
SPRING †
LOWER SPRING DISC (4" AND LARGER) * †
STEM NUT
STEM WASHER
DIAPHRAGM WASHER
(DIAPHRAGM DISC)
DIAPHRAGM*
UPPER STEM O-RING*
DISC RETAINER
(PLUNGER)
LOWER STEM O-RING*
DISC (SEAL RING)*
DISC GUIDE
(SEAL RING RETAINER)
STEM
SEAT SCREWS (8" AND LARGER) ‡
SEAT ‡
COVER STUDS (8" AND LARGER)
SEAT O-RING ‡
BODY
BODY PLUGS
STEM ASSEMBLY †
* RUBBER REPAIR KIT ITEMS
† COMPLETE REPAIR KIT ITEMS
‡ SEAT REPAIR KIT
VALVE
SIZE
(in)
COVER
(ft-lbs)
DIAPHRAGM
ASSEMBLY
(ft-lbs)
THREADED
SEAT
(ft-lbs)
SEAT
BOLTS
(ft-lbs)
1-1/4" 3.5 7.5 11 N/A
1-1/2" 3.5 7.5 11 N/A
2" 15 20-25 30 N/A
2-1/2" 25 25-35 60 N/A
3" 25 35-45 70 N/A
4" 55 40-50 85 N/A
6" 110 50-60 95 N/A
8" 120 60-70 N/A 7.4
10" 184 70-75 N/A 7.4
12" 200 110-115 N/A 7.4
14" 275 170-175 N/A 7.4
16" 360 230-240 N/A 7.4

ThePV-RLFPressureReliefValvemaybeinstalledinany
position.Theowdirectionisshownbelow.Flowgoesfromthe
narrow side to the wide side of the cast body.
Disassembly
Prior to disassembly, relieve all pressure in pilot system and
thenremovethePV-RLF.
1. Secure valve body and turn the adjustment screw all the
way out.
2.Nextremove8socketheadscrewsaroundthepilotbell
usinga5/32”hexkey.Removethebell,thespring,and2
spring discs.
3.Removethespacerandremovesmallgasketfromthe
bottom of the spacer. Use a 12mm socket or adjustable
wrench on the diaphragm and plunger nuts to disassemble
theplunger/diaphragmassembly.Unscrewoneendofthe
stem.
4.Atthispointslidetheplunger/diaphragmassembly
out of the valve spacer.
5.Usesoftjawsoratowelandplierstoclampthestem.
Becarefulnottoscratchthestemasthisisano-ring
surface. Use an adjustable wrench on the opposite nut
toremovetheremainingplunger/diaphragmassembly.
6. The parts removed from the disassembled diaphragm
and plunger assembly are a plunger, small washer, 2
o-rings , 2 nuts, a medium washer, a large washer,
diaphragm, and lock washer.
7. Use a small pin or nail to carefully remove the o-ring
on the inside through hole of the spacer.
8.Aftercompletedisassemblythoroughlycleanand
inspectallcomponentsbeforereassembly.Replace
parts as necessary after inspection.
9. The pilot seat generally does not need to be removed,
but if after inspection it requires replacement it can be
removedwitha1-1/16”socket.
PV-RLF Valve
Reassembly
ReassemblyofthePV-RLFisthereverseofdisassembly.
1. Carefully install a new o-ring in the through hole of
the spacer.
2.Placethemediumwasher(withroundouteredge
towardthediaphragm)onthesideofthestemwith
the chamfered tip.
3. Follow the washer by putting on a new o-ring, new
diaphragm,largewasher(withtheinnerstepagainstthe
diaphragm),lockwasher,and5/16”(chamferedside
awayfromdiaphragm)nutthenhandtighten.
4.Slidethestemthroughthespacerwiththediaphragm
assembly on the spacer side with a circular groove on
the top surface.
5.Ontheothersideofthestemplacethesmallwasher,
o-ring,plunger(withtherubberfacingawayfromthe
spacer),andnut.
DIRECTION
OF
FLOW
INLET OUTLET
ITEM DESCRIPTION
11/2"ReliefBody
2O-ringBunaNitrile,NSFListed
3ReliefPlungerAssy.
4Diaphragm O-ring
55/16"FlatWasher
6ReliefPilotStem
7O-ring,BunaNitrile,NSFListed
85/16"InternalToothLockWasher
9Spring Disc
10 Spring
11 PilotBell
12 3x8-16JamHexNut
ITEM DESCRIPTION
13 3/8-16AdjustmentBolt
14 AdjustmentCover
15 5/16-18DiaphragmNut
16 ReliefPilotUpperDiaphragmDisc,SS
17 10-32X1-1/2"SktHdCapScrew,SS
18 Tag
19 Diaphragm
20 ReliefPilotLowerDiaphragmWasher
21 ReliefPilotSpacer
22 SensingHoleGasket
23 O-ring,BunaNitrile,NSFListed
24 ReliefPilotSeat
Maintenance (PV-RLF Valve)
6. Use adjustable wrenches to tighten the plunger and
diaphragm nuts.
7. Place small gasket on bottom of valve spacer.
8.Installtheplungerassemblyontothebodywiththeplunger
sitting on the valve seat. The small rubber gasket on the
plunger side of the spacer must cover the sensing hole on
the pilot body.
9. Place a spring disk on the stem, then the spring, another
spring disk and bell.
10.Insertsocketheadcapscrewsintopilotbellholesand 
thread into valve body. Place model tag on the four screws
that straddle the body inlet. Tighten all screws in a cross
pattern.
11.Installadjustingscrewbyhandwithjamnut.Setvalveonce
reinstalledintopilotrysystem.Referto"Start-up"sectionon
page one for proper setting of relief pilot. For further assis-
tance or ordering replacement parts go to www.zurn.com
orcallproductsupport877-222-5356.
Table 1
13
11
10
17
20
7
21
6
23
3
24
2
15
1
5
4
18
12
4
19
16
22
9
15
8
14
9
ISZW207(REV.C6/17)
6
ZURN WILKINS
1747 Commerce Way, Paso Robles, CA 93446 Phone:[phone] Fax:[phone]
www.zurn.com
®