Specifications

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3) Twobasictypesoferrorscodesareshownonthedisplay:
• SoftLockoutCodes–Whenasoftlockoutoccurs,theboilerwillshutdownandthedisplaywillalternatebetween
thenumber“9”andtheletter“b”followedbyatwodigitservicecode.Alistofthesecodes,andtheirmeanings,is
showninTable14.3.Theboilerwillautomaticallyrestartoncetheconditionthatcausedthelockoutiscorrected.
• HardLockoutCodes–Whenahardlockoutoccurs,theboilerwillshutdownandthedisplaywillashtheletter
“E”followedbyatwodigitservicecode.Alistofthesecodes,andtheirmeanings,isshowninTable14.4.Oncethe
conditionthatcausedthelockoutiscorrected,theboilerwillneedtobemanuallyresetusingtheRESETbuttonon
thedisplay.
TABLE 12.3: BOILER STATUS
First Digit Boiler Status
0 Burner off - No call for heat or DHW
1 Pre-purge or post-purge
2 Ignition
3 Burner responding to call for heat
4 Burner responding to call for DHW
5 Checking air pressure switch
6 Burner off - Set point temperature has been reached
7 Call for heat ended. 10s heating post pump period
8 Call for DHW ended. 10s DHW post pump period
9 and b
Flashing
Burner off - on soft lockout. See Troubleshooting Section to
determine meaning of error code.
A Boiler responding to call from heating zone
H Burner on - Held in high re
L Burner on - Held in low re
4) Ifanoutdoorsensorisinstalled,theboilerwillautomaticallyadjusttheheatingzonesetpointtemperaturebasedonthe
outdoorresetcurveinFigure12.4.Themaximumsetpointisdenedbyparameter4(factorysetto180°F)whenthe
outdoortemperatureis0°Forbelow.Theminimumsetpointtemperatureshownis100°Fwhentheoutdoortemperature
is60°Forabove.Astheoutdoortemperaturefallsthesupplywatertargettemperatureincreases.Forexample,ifthe
outdoorairtemperatureis30°F,thesetpointtemperatureforthesupplywateris140°F.
5) Anindirectwaterheaterthermostatcanbeconnectedbetweenterminals7and8ontheterminalstrip.Whenthis
thermostatcloses,thecentralheatingcirculatorwillbeturnedoffandtheDHWcirculatorwillbeturnedon.
6) Anexternallimitcontrolcanbeinstalledbetweenterminals3and4ontheterminalstrip.Besuretoremovethejumper
betweenterminals3and4whenaddinganexternallimitcontroltothesystem.Iftheexternallimitopens,theboilerwill
shutdownanderrorcode“b26”willbedisplayed.Ifthelimitinstalledisamanualresettype,itwillneedtobereset
beforetheboilerwilloperate.
7) ThesequenceofoperationforaFCMSeriesboileronacallforheatfromathermostatisasdescribedbelow:
a) Whenpowerisrstturnedon,120VisprovidedtotheMCBA,thecombustionfanandtheLWCOtransformer.A
separate50VAtransformer,connecteddirectlytotheMCBA,powersallotherlowvoltagecircuits.
b) Fortherstfewsecondsafterpower-upthecontrolmodulegoesthroughaselfcheck.
c) Whenthereisacallforheat,thecontrolmodulecheckstomakesuretheairpressureswitchisopen.Ifitis,the 
combustionfanwillbeenergizedandwillrampuptoignitionspeed.Whentheairpressureswitchcloses,a10 
secondprepurgeisactivated.