Elson 150zd - Installation General Procedures; Pipe Fitting Specifications; Cold Water Feed Requirements; Cold Water Combination Valve Assembly

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PIPEFITTINGS
Allpipettingsaremadevia22mmcompression
ttingsdirectlytotheunit.Thettingsarethreaded
3/4”BSPmaleparallel,shouldthreadedpipe
connectionsberequired.
COLDFEED
A22mmcoldwatersupplyisrecommended,however,
ifa15mm(1/2”)supplyexists,whichprovidessufcient
ow,thismaybeused(althoughmoreownoise
maybeexperienced).
Astopcockorservicingvalveshouldbeincorporated
intothecoldwatersupplytoenablethecylinderand
itsassociatedcontrolstobeisolatedandserviced.
COLDWATERCOMBINATIONVALVEASSEMBLY
The2-piececoldwatercombinationvalveassembly
(seeFig.2)canbelocatedanywhereonthecold
water mains supply prior to the expansion vessel
(seeFig.6Page10)butthetwopiecesdonothave
tobeinstalledtogether.
The pressure reducing valve incorporates the
pressure reducer and strainer and the expansion valve
incorporatestheexpansionandcheckvalves.Ensure
that the valves are installed in the correct order
andorientation.Noothervalvesshouldbeplaced
betweentheexpansionvalveandthecylinder.A
connectioncanbemadebetweentheexpansionand
pressurereducingvalvestoprovideabalancedcold
waterconnection.Theexpansionvalveconnection
mustnotbeusedforanyotherpurpose.
DRAIN TAP
Asuitabledrainingtapshouldbeinstalledinthecold
watersupplytothecylinderbetweentheexpansion
valve(seeFig.6Page10)andtheheaterataslowa
levelaspossible.Itisrecommendedthattheoutlet
pointofthedrainpipeworkbeatleast1metrebelow
theleveloftheheater(thiscanbeachievedby
attachingahosetothedraintapoutletspigot).
EXPANSIONVESSEL
The expansion vessel accommodates expansion
thatresultsfromheatingthewaterinsidetheunit.
Theexpansionvesselispre-chargedat0.35MPa
(3.5bar).Theexpansionvesselmustbeconnected
betweentheexpansionvalveandthecylinder(see
Fig.6Page10).Thelocationoftheexpansion
vessel should allow access to recharge the pressure
asandwhennecessary,thiscanbedoneusing
anormalcarfootpump.Itisrecommendedthat
theexpansionvesselisadequatelysupported.An
expansionvesselwallmountingbracketissupplied
forthispurposeandshouldbetted.
SECONDARYCIRCULATION
Ifsecondarycirculationisrequireditisrecommended
thatitbeconnectedtothecylinderasshown (see
Fig.3page5)via a swept tee joint into the cold
feedtotheunit.Asweptteejointisavailableasan
accessory(ordercodeno.5133565).
Thesecondaryreturnpipeshouldbein15mmpipe
andincorporateacheckvalvetopreventbackow.
AsuitableWRASapprovedbronzecirculation
pumpwillberequired.Onlargesystems,dueto
theincreaseinsystemwatercontent,itmaybe
necessarytotanadditionalexpansionvesseltothe
secondarycircuit.Thisshouldbedoneifthecapacity
ofthesecondarycircuitexceeds10litres.
Pipe capacity (copper):
15mmO.D.=0.13l/m(10litres=77m)
22mmO.D.=0.38l/m(10litres=26m)
28mmO.D.=0.55l/m(10litres=18m)
NOTE:SecondarycirculationisNOTrecommendedfor
directelectricunits.
OUTLET
Thehotwateroutletisa22mmcompressiontting
locatedatthetopofthecylinder.Hotwaterdistribution
pipeworkshouldbe22mmpipewithshortrunsof
15mmpipetoterminalttingssuchassinksand
basins.Pipesizesmayvaryduetosystemdesign.
INSTALLATION GENERAL
Fig.2:Coldwatercombinationvalveassembly
Fig.3:Secondarycirculationconnection