MechanicalInstructions
SiteSelection
ReviewtheNEMATyperatingoftheheaternotedonthe
HEATREXApplicationData.Donotinstallaheaterinanareanot
consistentwithitsrating.
Allowsufficientfreespacearoundheaterinstallationsite.Work
spaceforheatermaintenanceshouldbeatleastthreefeetin
frontandoneithersideoftheheater.Theminimumpullspace
fortheheatingelementinstallationorremovalfromthe
pipe/tubeshouldbeatleastfourfeet.Theheatingelementis
designedtobeflexibleandcanbecurvedifnecessary.
Electricheatersarecapableofdevelopinghightemperatures.
Therefore,extremecareshouldbetakento
avoidmountingheatersinanatmospherecontaining
combustiblegases,vapors,dusts,orfibersunlessproperly
markedassuitableforthecondition.
HeaterOrientation
Thisstyleofheaterisintendedforhorizontaluseonly.Theopen
coilresistancewiremustnotbemountedinaverticalorientation
orfailurecouldoccurfromthecoilsagging.
Theheatermustbemountedplumbhorizontallytoassure
properoperation.
Thermalexpansionoftheheaterpipesmustbeconsideredwhen
locatingtheheater.Itcanbeapproximatedas:
Pipe
Length
(Inches)
x.00001x
MaxPipe
Operating
Temp(°F)
‐70°F
2
Iftheheaterisinstalledinapressurizedtank,areliefvalvemust
beinstalled.Asaminimum,thevalvemustbesizedtorelieveat
arateequaltotheratethattheheatercanthermallyexpand
fluidinthetank.
PipeInstallation
OnheaterpipesprovidedwithANSIflangedconnections,take
caretopreventscratchingtheflangefaces.HEATREXsuppliesa
non‐asbestosnitrilebondedfiberflangegasketunlessotherwise
requested.Theusermustconfirmthatthegasketissuitablefor
theapplication.Theusermustsupplyhighstrengthstudsorbolts
andnuts,suchasA‐193GR.B7andA194GR.2H,ratedforthe
designconditions.Boltsmustbeproperlyinstalledandtightened
topreventleaks.
Whenheaterpipesareweldeddirectlytotheuser’stankwall,
removetheheatingelementfromthepipebeforewelding.Refer
tothefollowinginstructionsforhandlingandremovingheating
elements.
Heaterpipesmustbesupportedinsidetheuser’stank.Supports
mustnotpreventthepipesfromthermallyexpanding.Supports
shouldbelocatedonamaximumspacingof10feet.
Wherebuildupofsolidsinthebottomofthetankisexpected,
thepipemustbelocatedabovethatlevel.Thepipemustalsobe
locatedbelowtheminimumoperatingfluidlevelofthetank.
Heaterpipesmustbeperfectlycleanbeforeinstallationof
heatingelement.Useonlyacleandryclothtoclean.Neveruse
alubricant.Compressedairwithalongwandmaybeusedto
removeceramicchips,etc.
IftheheaterpipeisnotsuppliedbyHEATREX,ensurethepipe
lengthiscorrectbymeasuringtheheatingelementoveralllength
(OAL),thecoldlengthfromthestartofthecoiledwiretothe
frontendoftheheatingelement(CL),andthelengthofthe
heaterpipenotincludingthepipecap(PL).
ThepipelengthPLmustbegreaterthanorequaltoOAL.When
locatingtheheaterpipeinthetank,thedistancefromthefront
endofthepipetotheexteriortankwallmustbelessthanor
equaltoCLtoensuretheheatedareaisinthefluid.
HeatingElementInstallation&Removal
Toremovetheheatingelementfromaheaterpipeorshipping
tube,firstremovethefasteningnutattheterminalend.Hold
theceramicinsulatorfirmlyinordertoavoidunduepressureon
theceramicandpossiblebreakage.Ifobstructionsare
encountered,rotatetheheaterslightlybackandforthwhile
pullingout.
Sinceheatingelementscanbeofconsiderablelength,itmaynot
alwaysbepossibletoremovetheelementinastraightline,due
tospacelimitations.Sincetheelementbarisflexible,the
elementmaybecurvedonaradiusof4feetminimum.Itis
recommendedthatatleast2peoplebeusedforthisprocedure,
inordertoavoidbreakingtheceramics.
Aftertheelementbarhasbeenremoved,itshouldbecarefully
stretchedoutonacleantableforinspection.Brokenceramics
mustbereplacedandburnspotsshouldbecleanedwithadry
cleanpaperorclothtowel.Oilorothercontaminationonthe
heaterwillcauseafailure.
Wheninstallingtheheatingelementintotheheaterpipe,reverse
thestepsnotedabove.
Heaterpipesmustbeperfectlycleanbeforeinstallationof
element.Useonlyacleandryclothtoclean.Neverusea
lubricant.Compressedairwithalongwandmaybeusedto
removeceramicchips,etc.
Theheatingelementintendedonlytobeinstalledwiththesheet
metalstriponthebottom.Donotrotatetheheaterinthepipe.
CAUTION -Hazard of Electric Shock
Heatersmustbeboltedintopositionattheterminalend
topreventmovement,whichcouldallowtheheaterto
shortoutagainstthepipe.
Seefiguresattachedformountingconfigurations.
Thermalinsulationmustbeinstalledbetweenthefirstfew
ceramicsinthe“cold”sectionoftheheaterwheretheresistance
wireisnotcoiled.Aloosefillcerafiber(HEATREXP/N1008466)
orequal,ratedfor2000°F,ispreferred.Theinsulationmustbe
freeofmoistureorcontaminationinordertoprovideelectrical
isolation.Theinsulationisnecessarytoallow90°Cratedfield
wiring.
