402M•Series14RemotePanelwithS/O/WSwitch,Lights&40-80°FDial&RoomOverride(Modular)

DescriptionofTemperatureControl

• 402M-MaxitrolSeries14ElectronicModulatingDischargeTemperatureControlwithRemotePanelandRoomOverrideThermostat

• SingleRange-40°Fto80°FDischargeTemperatureSet-PointMountedinRemotePanel,RoomOverrideMountedinSeparateRemotePanel

• DischargeSensorMountedinBlower• DischargeRemotePanelIncludesSummer/Off/WinterSwitch,andIndicatorLights

ApplicationsWheretemperedmake-upairisrequiredforbothindoorairqualityandtoreplaceanexhaustloadinafacilitywhereaprimaryheatingsourceisalreadyinplace.

HeaterType100%OutsideAirSingleSpeedorVariableAirVolume(VAV)IndustrialUnit

SequenceofOperationsWiththedisconnectinONpositionandtheSUMMER/OFF/WINTERswitch(SW-04)inWINTERposition,powerissuppliedtothedampermotor(MT-02),ifequipped.

WhenthedampermotorapproachestheOPENposition(approximately70%),thedamper-endswitch(SW-03)closesenergizingtheblowermotorstartercontactor(ST-01)andpoweringtheblowermotor(MT-01).Aftertheblowerisenergizedthe“BlowerOn”light(LT-01)willilluminateontheremotepanel.

Iftheunitisequippedwiththelow-temperaturelimitcontrol(TS-01),aftertenminutes,thelow-temperaturelimitcontrolshutsdowntheunitifthedischargetemperaturedoesnotreachtheminimumset-pointonthelow-temperaturelimitcontrol.UponshutdownTS-01willenergizethe“LowTemperature”lightontheremotepanel(LT-05)andthedamperwillclose.

Iftheunitisequippedwithasmokedetector(TS-07),thesmokedetectorwillshutdowntheunitifsmokeisdetected.

Ifanexhaustfanstartercoilistiedintotheexhaustfaninterlock(RE-E),theexhaustfanwillturnon.

Iftheunitisequippedwithacloggedfilterswitch(PS-05),thepressuredropacrossthefilterswillbemonitored.Ifthepressuredropexceedstheset-point,PS-05willilluminatethe“CloggedFilter”lightontheremotepanel(LT-06).

Thelowairflowswitch(PS-01)andthehighairflowswitch(PS-02)mustbeprovenbeforetheFireye(FSC-01)canbeenergized.Therealsomustbeacallforheatfromtheintakeairsensor(TS-03)andthehightemperaturelimitswitch(TS-02)mustnotbeactivated.TheFireyeflamesafetycontrolwillmonitortheflameviatheflamerod(FR-01)andsendasignaltothesparkplugandpilotgasvalve(VA-01).

(Note:thehightemperaturelimitswitchwillmonitortheairtemperatureandshutdowntheburnerifthetemperaturesetpointisexceeded.Thehightemperaturelimitwillrequireamanualreset.)

(Note:whentheremotepanelisinSUMMERpositiontheburnerislockedout)

Ifequippedwiththemodularpackagedunitoption,andtheintakeairsensor(TS-03)doesnotcallforheat,andthecoolingthermostat(TS-06)callsforcooling,thecompressorswillbeenergized.Thefirststageofcoolingwillbefactorysettoactivateat85°Fandthesecondstagewillactivateiftheambientairtemperaturerisesanother10°Fabovethefirststageofcooling.

Ifequipped,theoptionallowandhighgaspressureswitches(PS-03&PS-04)willbeenergized.Ifthegaspressureisnotbetweentheset-pointstheburnerwillturnoffandrequireamanualreset.

Afterthepilotgasvalveopensthe“BurnerOn”light(LT-02)willilluminateontheremotepanel.Aftertheflamerod(FR-01)provesflamethemainvalve(VA-02)opens.Iftheflameroddoesnotproveafter3ignitioncycles,theburnerwillshutoffandthe“FlameFailureLight”(LT-03)willilluminateontheremotepanel.

Thetemperaturecontrolsystem’samplifier(MA-01)receivestwosignals,onefromthedischargesensorandonefromtheremotepanel.Theremotepanelsendsasignalbasedeitheronthesetpointfromtheremotepanelorfromtheroomthermostat(TS-07).TheamplifiercontinuallycomparesthesesignalsandwhenheatisrequiredtheamplifierwillsendaDCvoltagetothemodulatingvalve(VA-03).AstheDCvoltagefromtheamplifierincreasesthemodulatingvalvewillopen,allowingmoregastoflow.Iftheroomthermostatisnotsatisfied,ahighfiresignaloverridestheremotepanelsetpointforcingtheunitintohighfireuntilthespacetemperaturethermostatissatisfied.

AdditionalSequenceofOperationforVAVunits

VAVwithStaticPressureControl

TheVFDisenergizedafterthedampermotorswitch(SW-03).

Thephotohelic,usedtomonitortheindoorairpressure,sendsasignaltotheVFDprovingthattheindoorpressureissatisfied,positive,ornegative.Basedonthissignal,theVFDalterstheHZtotheblower.Dependingonthesignalfromthephotohelic,theVFDwilldothefollowing:

• Ifthespaceissatisfied,theVFDwillmaintaincurrentoperation• Ifthespaceisnegative,theVFDwillrampuptorebuildthepressureinthespace• Ifthespaceispositive,theVFDwillmodulatedowntoreducethepressureinthespace

VAVwithManualPotentiometer

TheVFDisenergizedafterthedampermotorswitch(SW-03).

ThemanualpotentiometeraltersthespeedoftheVFDbyalteringtheHZtotheblower.

VAVwithConstantSpeedControlorAnalogInputControl

TheVFDisenergizedafterthedampermotorswitch(SW-03).

TheVFDcanoperatebyeitherananaloginputorpresetspeeds.

Ifanaloginputisrequired,ananaloginputsignalissenttotheVFDbyanexternalsource,whichwilldirectlycontrolthesignaltotheblower.

Ifpresetspeedsarerequired,anexternalswitchcanbeusedtomanuallyadjustbetweenprogrammedspeedsintheVFD.TheVFDwillsendasignaltotheblower.