Specifications

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2) Circulator(Required)-UsuallyatleasttwocirculatorswillberequiredtoproperlyinstallaFCMSeriesboiler.Seethe
previoussectionforinformationonsizingthecirculators.
3) ExpansionTank(Required)-Ifthisboilerisreplacinganexistingboilerwithnootherchangesinthesystem,the
oldexpansiontankcangenerallybereused.Iftheexpansiontankmustbereplaced,consulttheexpansiontank
manufacturer’sliteratureforpropersizing.
4) FillValve(Required)-Eitheramanualorautomaticllvalvemaybeused.Theideallocationforthellisatthe
expansiontank.
5) Automatic
AirVent(Required)-Atleastoneautomaticairventisrequired.Manualventswillusuallyberequiredin
otherpartsofthesystemtoremoveairduringinitialll.
6) ManualResetHighLimit(Requiredbysomecodes)-ThiscontrolisrequiredbyASMECSD-1andsomeothercodes.
Installthehighlimitintheboilersupplypipingjustabovetheboilerwithnointerveningvalves.Setthemanualreset
highlimitto200°F.WirethelimitperFigures10.1&10.2intheWiringsection.
7) Flow
ControlValve(Required)-Theowcontrolvalvepreventsowthroughthesystemunlessthecirculatoris
operating.Flowcontrolvalvesareusedtopreventgravitycirculationor“ghostows”incirculatorzonesystems
throughzonesthatarenotcallingforheat.
8) Isolation
Valves(Recommended)-Isolationvalvesareusefulwhentheboilermustbedrained,astheywilleliminate
havingtodrainandrelltheentiresystem.
9) DrainValve(Required)-Thedrainvalveisinstalledonthereturnteelocatedinthelowervestibulecompartmentas
showninFigure9.2.
10) LowWaterCut-off(Required)-Thelowwatercut-offsuppliedwiththisboilermustnotberemoved.
D. Piping for Special Situations
1) Systemscontainingoxygen-Manyhydronicsystemscontainenoughdissolvedoxygentocauseseverecorrosion
damagetoanaluminumboilersuchastheFCM.Someexamplesinclude:
• Radiantsystemsthatemploytubingwithoutanoxygenbarrier.
• Systemswithroutineadditionsoffreshwater.
• Systemswhichareopentotheatmosphere.
 Iftheboileristobeusedinsuchasystem,itmustbeseparatedfromtheoxygenatedwaterbeingheatedwithaheat
exchangerasshowninFigure9.10.Consulttheheatexchangermanufacturerforproperheatexchangersizingaswellas
owandtemperaturerequirements.Allcomponentsontheoxygenatedsideoftheheatexchanger,suchasthepumpand
expansiontank,mustbedesignedforuseinoxygenatedwater.
2) Piping
withaChiller-Iftheboilerisusedinconjunctionwithachiller,pipetheboilerandchillerinparallelasshownin
Figure9.11.Useisolationvalvestopreventchilledwaterfromenteringtheboiler.
3) Air Handlers-Wheretheboilerisconnectedtoairhandlersthroughwhichrefrigeratedairpasses,useowcontrol
valvesintheboilerpipingorotherautomaticmeanstopreventgravitycirculationduringthecoolingcycle.