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WATER QUALITY AND BOILER WATER ADDITIVESWATER QUALITY AND BOILER WATER ADDITIVES
IMPORTANT NOTEIMPORTANT NOTE
Thisboilerisequippedwithanaluminumheatexchangerthatcanbeseriouslydamagedbyfailuretofollow
thefollowingguidelines:
Flushthesystembeforeconnectingtheboiler
Flushthesystembeforeconnectingtheboiler
-Inareplacementinstallation,ushingthesystemwillremove
Flushthesystembeforeconnectingtheboiler-Inareplacementinstallation,ushingthesystemwillremoveFlushthesystembeforeconnectingtheboiler
sediment,solderux,andtracesofoldboileradditives.Evenifthesystemisnew,donotomitthisstep-new
systemswillcontainsolderuxandmayevencontainsediment.
Makesurethatthesystemistight
Makesurethatthesystemistight
Makesurethatthesystemistight-Makesurethatthesystemistight
This is the single most important guideline
.Tapwatercontainsdissolved
oxygenwhichcausescorrosion.Inatightsystem,thisoxygencomesoutofsolutionandisquicklyremoved
fromthesystemthroughtheautomaticairvent.Thesystemthenremainsessentiallyfreeofoxygen.Ifthe
systemisnottight,however,frequentadditionsofmake-upwatercanexposetheheatexchangertooxygenon
acontinuousbasis.Inaddition,frequentadditionsofhardmake-upwatercancausecalciumdepositstocollect
intheheatexchanger,causingseveredamage.
Tominimizeadditionsofmake-upwater:
• Inspectthesystemthoroughlyforleaksbeforeplacingitinservice.
• Ifthesystemincludesundergroundpiping,orotherpipinginwhichaleakmightgoundetected,consider
isolatingtheboilerfromthesystemwithaheatexchanger.Alternatively,considerinstallingawatermeter
inthelllinetorecordadditionsofmake-upwater.
• Makesurethattheexpansiontankisproperlysizedandingoodcondition.Ifitisnot,thereliefvalvemay
openfrequently,resultinginregularadditionsofmake-upwater.
RadiantTubingandOxygenBarriers
RadiantTubingandOxygenBarriers
-Evenifthesystemistight,oxygencanbeintroducedintothesystem
throughsometypesofnon-metallictubingusedinradiantorsnowmeltsystems.Othernon-metallictubingis
equippedwithanoxygenbarriertopreventmigrationofoxygenintothewater.Iftheboileristobeinstalledin
asystemcontainingnon-metallictubingwithoutanoxygenbarrier,itmustbeisolatedfromtheboilerwitha
heatexchangerasshowninFigure9.10.
-Donotuseantifreezeunlessabsolutelynecessary.Ifantifreezemustbeused,theonlypermitted
• FernoxCHPinvirginpropyleneglycol(availablefromU.S.Boiler)
Ifeitheroftheaboveantifreezesareused,testtheboilerwateronanannualbasistoensurethattheantifreeze
remainsnon-corrosive.ThisisdonewithFernoxtestkitI-TK(availablefromU.S.Boiler).
OtherAntifreezesandBoilerAdditives
-Donotaddotheradditivesunlesstheyarespecicallyapprovedin
wiringbyU.S.Boilerforusewiththisboiler.Thisincludesother“aluminumsafe”antifreezes.
-MaintainthePHinthesystembetween6.5and8.5.