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NATE EXAM: AIR CONDITIONING AND
HEAT PUMPS TEST WITH ALL
ANSWERS GRADED A+
WhichTofTtheTfollowingTfactorsTaffectsTaTcustomer'sTlevelTofTcomfort? a.TAirTmovement b.THumidity c.TTemperature d.TAllTofTtheTaboveT-TcorrectTanswer- dT(AllTofTtheTabove:TairTmovement,Thumidity,Ttemperature) ATcoolingTloadTcalculationTestimatesTtheTsensibleTheatTgainTofTaTstructure.TTheTmaxim umTsensibleTcapacityTofTaTcooling-onlyTsystemTshouldTbeTwithinT____ %TofTthisTcalculatedTvalue. a.T±10% b.T+10% c.T+15% d.T+30%T-TcorrectTanswer-cT(+15%) TheTmaximumTsensibleTcoolingTcapacityTofTaTheatTpumpTshouldTbeTwithinT____ %TofTtheTcalculatedTsensibleTheatTgainTofTaTstructureTwithTaTlargeTheatingTload. a.T±10% b.T+15% c.T-25% d.T+25%T-TcorrectTanswer-dT(+25%) TheTcombinedToutputTofTaTheatTpumpTandTitsTauxiliaryTheatTshouldTnotTexceedTtheTcalc ulatedTheatTlossTofTaThomeTbyTmoreTthanT____%. a.T10% b.T15% c.T20% d.T25%T-TcorrectTanswer-bT(15%) WhatTamountTofTauxiliaryTelectricTheatTisTneededTwhenTtheToutputTofTaTheatTpumpTonTa TdesignTdayTequalsT18,800TBtuhTandTtheTheatTlossTofTaThomeTisT29,700TBtuh? a.T2.1TkWh
b.T3.2TkWh c.T5.0TkWh d.T10.9TkWh Note:T3,413TBtu/kWT-TcorrectTanswer-bT(3.2TkWh) TheTthreeTprocessesTthatTtransferTheatTenergyTareTconduction,Tconvection,TandT____. a.Tconcentration b.Tradiation c.Trefraction d.TstaticTpressureT-TcorrectTanswer-bT(radiation) HeatTtransferTthatToccursTwhenTsubstancesTofTdifferentTtemperaturesTareTinTcontactTwi thTeachTotherTisTcalledT____. a.Tconcentration b.Tconduction c.Tconvection d.TradiationT-TcorrectTanswer-bT(conduction) WhatTeffectTdoesTraisingTtheTpressureTinTaTsealedTsystemThaveTonTrefrigerant? a.TItTbecomesTmoreTdifficultTtoTsubcoolTtheTliquidTrefrigerant b.TItTbecomesTmoreTdifficultTtoTsuperheatTtheTrefrigerantTvapor c.TTheTrefrigerant'sTboilingTpointTdecreases d.TTheTrefrigerant'sTboilingTpointTincreasesT-TcorrectTanswer- dT(TheTrefrigerant'sTboilingTpointTincreases) WhatTisTtheTprimaryTdangerTtoTpeopleTnearTanTaccidentalTrefrigerantTreleaseTorTspill? a.TBlurredTvisionTcausedTbyTtheTrefrigerantTvaporTcomingTinTcontactTwithTtheTeyes b.TChangesTinTweatherTpatternsTcausedTbyTglobalTwarming c.TDamageTtoTtheTfoodTchainTcausedTbyTdecreasedTozoneTlevelsTinTtheTstratosphere d.TSuffocationTcausedTbyTtheTheavierTrefrigerantTdisplacingToxygenTinTtheTairT- TcorrectTanswer- dT(SuffocationTcausedTbyTtheTheavierTrefrigerantTdisplacingToxygenTinTtheTair) TheTmaximumTtemperatureTatTwhichTrefrigerantTmayTbeTstoredTisT____°FTwhenTtheTco ntainerTisTnoTmoreTthanT____%TfullTofTliquidTbyTvolume. a.T120°F,T60% b.T125°F,T60% c.T125°F,T80% d.T135°F,T80%T-TcorrectTanswer-cT(125°F,T80%) BoilingTofTtheTrefrigerantToccursTinTwhichTsystemTcomponent? a.TCompressor b.TCondenser
b.TWithTwaterTcirculatedTthroughTtubingTwrappedTaroundTtheTcompressorTshell c.TWithTsuctionTvaporTdrawnTfromTtheTevaporator d.TWithTaTcombinationTofTairTandTwaterT-TcorrectTanswer- cT(WithTsuctionTvaporTdrawnTfromTtheTevaporator) HeatTpumpTcompressorsTsometimesTrunThotterTthanTcompressorsTusedTinTcooling- onlyTunitsTbecauseTheatTpumpTcompressorsT____. a.TexhibitTlowTrefrigerantTdensityTatTlowTsuctionTpressuresTduringTtheTheatingTcycle b.TpumpTliquidTrefrigerantTduringTtheTcoolingTcycle c.TmustTpreventTiceTformationTduringTtheTdefrostTcycle d.TmustTheatTindoorTspacesTinTtheTwinterT-TcorrectTanswer- aT(exhibitTlowTrefrigerantTdensityTatTlowTsuction) WhenTisTaTcrankcaseTheaterTmostTneeded? a.TEarlyTinTtheTmorningTduringTtheTcoolingTcycle b.TWhenTtheTcompressorTisToperatingTinTveryTcoldTwinterTweather c.TWhenTtheTcompressorTisToperatingTinTveryThumidTconditions d.TWhenTtheTcompressorTisToffT-TcorrectTanswer-dT(WhenTtheTcompressorTisToff) WorkTdoneTonTtheTrefrigerantTinTtheTcondenserTisTtransferredTasT____. a.TlatentTheat b.TsensibleTheat c.TspecificTheat d.TbothTsensibleTandTlatentTheatT-TcorrectTanswer-dT(bothTsensibleTandTlatentTheat) WhyTareTmoreTcircuitsTneededTinTtheToutdoorTcoilsTusedTinTheatTpumpsTthanTinTtheTcon denserTcoilsTusedTinTcooling-onlyTunits? a.TToTkeepTtheTpressureTdropTacrossTtheToutdoorTcoilThigh b.TToTkeepTtheTpressureTdropTacrossTtheToutdoorTcoilTlow c.TToTprovideTmoreTsubcoolingTduringTtheTcoolingTcycle d.TToTprovideTmoreTsubcoolingTduringTtheTheatingTcycleT-TcorrectTanswer- bT(ToTkeepTtheTpressureTdropTacrossTtheToutdoorTcoilTlow) WhatTisTtheTtypicalTwaterTflowTrateTperTtonTofTcoolingTforTwater- sourceTheatTpumpsToperatingTinTclosed-loopTsystems? a.T3.0TgpmTperTton b.T2.5TgpmTperTton c.T2.0TgpmTperTton d.T1.5TgpmTperTtonT-TcorrectTanswer-aT(3.0TgpmTperTton) WhatTtoolTshouldTbeTusedTtoTshortenTaTcapillaryTtube? a.TATpairTofTpliersTwithTside-cutterTedges b.TATsmallTtubingTcutter c.TAnyTtubingTcutterTapprovedTforTuseTonTrefrigerantTtubing
d.TATtriangularTorTknife-edgeTfileT-TcorrectTanswer-dT(ATtriangularTorTknife-edgeTfile) WhichTpressureTinTaTTEVTisTtheTopeningTpressure? a.TBulbTpressure b.TEvaporatorTpressure c.TSpringTpressure d.TATcombinationTofTbulbTandTspringTpressuresT-TcorrectTanswer-aT(BulbTpressure) WhatTaffectTdoesTaTlowTrefrigerantTchargeThaveTonTreversingTvalveToperation? a.TItTcausesTtheTsliderTtoToverheat b.TItTcreatesTaThissingTsoundTinTtheTreversingTvalve c.TItTincreasesTtheTchanceTthatTtheTreversingTvalveTwillTnotTbeTableTtoTtransferTproperly d.TItThasTnoTeffectTonTreversingTvalveToperationT-TcorrectTanswer- cT(ItTincreasesTtheTchanceTthatTtheTreversingTvalveTwillTnotTbeTableTtoTtransferTproperly) WhenTaddingTaTheatTpumpTtoTanTexistingTfossil- fuelTfurnace,TanTinstallerTmustTdoTallTofTtheTfollowingTexceptT____. a.TaddTaTcontrolTtoTpreventTtheTheatTpumpTandTfurnaceTfromToperatingTatTtheTsameTtim eTduringTnormalTheating b.TconfirmTthereTisTadequateTclearanceTaroundTtheToutdoorTsectionTforTgoodTairTflow c.TlevelTtheTindoorTcoil'sTcondensateTpanTtoTensureTproperTdrainageTofTcondensateTwat er d.TmakeTsureTthatTtheTnumberTofTfinsTperTinchTofTtheTnewTcoilsTequalsTthatTofTtheTreplac edTcoilsT-TcorrectTanswer- dT(makeTsureTthatTtheTnumberTofTfinsTperTinchTofTtheTnewTcoilsTequalsTthatTofTtheTreplac edTcoils) WhatTisTtheTpurposeTofTaTreceiver? a.TItTpreventsTliquidTrefrigerantTfromTsluggingTtheTcompressor b.TItTremovesTheatTfromTrefrigerantTvapor c.TItTreturnsToilTtoTtheTcompressorTatTaTrateTtheTcompressorTcanTtolerate d.TItTstoresTliquidTrefrigerantT-TcorrectTanswer-dT(ItTstoresTliquidTrefrigerant) WhatTisTtheTtypicalTstorageTlifeTofTmodernTrefrigerants? a.T 5 TtoT 10 Tyears b.T 10 TtoT 20 Tyears c.T 20 TtoT 30 Tyears d.TModernTrefrigerantsThaveTanTindefiniteTstorageTlifeT-TcorrectTanswer- dT(ModernTrefrigerantsThaveTanTindefiniteTstorageTlife) WhichTofTtheTfollowingTshouldTbeTusedTtoTleak-testTrefrigerantTtubing? a.TCompressedTair b.TDryTnitrogen c.TOxygen
a.TreciprocatingTcompressorsTusedTwithTTEVs b.TrotaryTcompressorsTusedTwithTfixedTmeteringTdevices c.TscrollTcompressorsTusedTwithTTEVs d.Tthree-phaseTcompressorTusedTwithTfixedTmeteringTdevicesT-TcorrectTanswer- aT(reciprocatingTcompressorsTusedTwithTTEVs) AT24-VTtransformerTwithTaT40-VATratingTcanToperateTsafelyTwithTaTcurrentTofT____. a.T6.0TmA b.T960.0TmA c.T0.6TA d.T1.67TAT-TcorrectTanswer-dT(1.67TA) SomeTelectromechanicalTthermostatsTmustTbeTconnectedTtoTbothTsidesTofTtheTtransfor merTinTorderTtoTpowerTtheT____. a.TcoolingTanticipator b.TdisplayTlightsTonTtheTsubbase c.TheatTanticipator d.TmicroprocessorT-TcorrectTanswer-bT(displayTlightsTonTtheTsubbase) ATcoolingTanticipatorTinTtheTcontrolTcircuitTisTconnectedTinT____TwithTtheT____TswitchTof TtheTthermostat. a.Tparallel,Tcooling b.Tparallel,Theating c.Tseries,Tcooling d.Tseries,TheatingT-TcorrectTanswer-aT(parallel,Tcooling) AccordingTtoTOhm'sTLaw,TwhatTwillThappenTifTvoltageTtoTaTheaterTelementTisTincreasedT byT10%? a.TTheTBtuhToutputTwillTincreaseTbyT5% b.TTheTcurrentTdrawTwillTdecreaseTbyT10% c.TTheTcurrentTdrawTwillTincreaseTbyT10% d.TTheTheaterTwillToverheatT-TcorrectTanswer-cT(theTcurrentTdrawTwillTincreaseTbyT10%) WhenTairTflowTthroughTanTelectricTheaterTisTnotTsufficient,TtheTtechnicianTwillTobserveT_ ___. a.TfusibleTlinksTglowingTredTorTorange b.TheaterTelementsTglowingTredTorTorange c.Thigher-than-normalTvoltageTreadings d.Tlower-than-normalTvoltageTreadings SeeTpageT 78 T-TcorrectTanswer-bT(heaterTelementsTglowingTredTorTorange) WhichTofTtheTfollowingTcombinationTofTmeasurementsTindicatesTanTopenTheaterTeleme nt?
a.TCurrentTdrawTthroughTtheTheaterTelementsTwithTnoTvoltageTtoTtheTheater b.TVoltageTtoTtheTheaterTwithTcurrentTdrawTthroughTtheTheaterTelements c.TVoltageTtoTtheTheaterTwithTnoTcurrentTdrawTthroughTtheTheaterTelements d.TvoltageTtoTtheTheaterTwithTresistanceTmeasuredTbyTanTohmmeterT-TcorrectTanswer- cT(VoltageTtoTtheTheaterTwithTnoTcurrentTdrawTthroughTtheTheaterTelements) WhichTofTtheTfollowingTfunctionsToccurTwhenTaTheatTpumpTgoesTintoTaTdefrostTcycle? a.TTheTauxiliaryTheatTcomesTon,TtheToutdoorTfanTstopsTrunning,TandTtheTreversingTvalv eTswitchesTtoTtheTcoolingTmode b.TTheToutdoorTfanTstopsTrunningTandTtheTreversingTvalveTswitchesTtoTtheTcoolingTmod e c.TTheTreversingTvalveTswitchesTtoTtheTcoolingTmodeTandTtheTauxiliaryTheatTcomesTon d.TTheTreversingTvalveTswitchesTtoTtheTheatingTmode,TtheToutdoorTfanTstopsTrunning,Ta ndTtheTauxiliaryTheatTcomesTonT-TcorrectTanswer- aT(TheTauxiliaryTheatTcomesTon,TtheToutdoorTfanTstopsTrunning,TandTtheTreversingTvalv eTswitchesTtoTtheTcoolingTmode) WhatTinternalTvoltageTisTlikelyTtoTbeTmeasuredTinTanTelectronicTairTcleaner? a.T 24 TV b.T 120 TV c.T 380 TV d.T5,000TV SeeTpageT 81 T-TcorrectTanswer-dT(5,000TV) WhatTprecautionTmustTyouTtakeTwhenTinstallingTaTdual-fuelTsplitTsystem? a.TTheTcontrolTsystemTmustTnotTallowTtheTheatTpumpTandTfurnaceTtoToperateTatTtheTsa meTtimeTduringTnormalTheatingTcycle b.TTheThigh- limitTswitchTonTtheTheatTpumpTmustTbeTreplacedTwithToneTthatThasTaTlowerTtemperature Tsetting c.TTheThigh- limitTswitchTonTtheTheatTpumpTmustTbeTreplacedTwithTonTthatThasTaThigherTtemperatureT setting d.TTheTlimitTcontrolTonTtheTfurnaceTmustTbeTreplaceTwithToneTthatThasTaTmanualTresetT- TcorrectTanswer- aT(TheTcontrolTsystemTmustTnotTallowTtheTheatTpumpTandTfurnaceTtoToperateTatTtheTsa meTtimeTduringTnormalTheatingTcycle) WhatTproblemTisTlikelyTtoToccurTifTaTproperTtrapTisTnotTusedTonTtheTcondensateTdrainTfor TaTdraw-throughTunit? a.TCondensateTwaterTwillTnotTdrainTproperlyTandTwillTbackTupTaboveTtheTprimaryTdrain b.TConditionedTsupplyTairTwillTescapeTthroughTtheTcondensateTdrainpipe c.TIceTwillTaccumulateTonTtheTevaporatorTcoil d.TStressTonTtheTconnectionTfittingTatTtheTevaporatorTwillTcauseTtheTpipeTtoTcrack
SeeTpageT 100 T-TcorrectTanswer-cT(NeutralTflame) WhyTmustTyouTexerciseTspecialTcareTwhenTyouTbendTsoft-drawnTrefrigerantTtubing? a.TAnyTdistortionTofTtheTtubingTdiameterTcreatesTaTrestrictionTtoTrefrigerantTflowTthatTred ucesTsystemTcapacity b.TCopperTflakesTcanTcomeTlooseTfromTinteriorTsurfacesTofTtheTtubingTifTitTisToverbent c.TOverbendingTtheTtubingTmakesTitTdifficultTtoTslideTonTtheTclose-cellTinsulation d.TTheTrefrigerationTflowTrateTincreasesTifTtubingTisToverbent,TmakingToilTreturnTimpossi bleT-TcorrectTanswer- aT(AnyTdistortionTofTtheTtubingTdiameterTcreatesTaTrestrictionTtoTrefrigerantTflowTthatTred ucesTsystemTcapacity) TheTevacuationTofTaTrefrigerantTcircuitTisTconsideredTcompleteTwhenTaTvacuumTofT____ TcanTbeTmaintained. a.T 200 Tmicrons b.T 350 Tmicrons c.T 500 Tmicrons d.T1,000TmicronsT-TcorrectTanswer-cT(500Tmicrons) AsTtheTlengthTofTelectricalTwireTincreases,TitsTresistanceT____TwhileTtheTtemperatureTisT maintainedTatTaTconstantTlevel. a.Tdecreases b.Tincreases d.TremainsTunchanged c.TvariesTunpredictablyT-TcorrectTanswer-bT(increases) WhatTisTtheTthermalTbalanceTpointTofTaTheatTpumpTsystem? a.TTheTindoorTairTtemperatureTatTwhichTtheTblowerTfanTspeedTmustTbeTincreasedTinTord erTtoTmaintainTtheTspaceTtemperatureTsetpoint b.TTheToutdoorTairTtemperatureTatTwhichTtheTheatTpumpTinitiatesTaTdefrostTcycle c.TTheToutdoorTairTtemperatureTatTwhichToutputTofTtheTgasTfurnaceTinTaTdual- fuelTapplicationTequalsTtheTheatTlossTofTtheThome d.TTheToutdoorTairTtemperatureTatTwhichTtheToutputTofTtheTheatTpumpTequalsTtheTheatTl ossTofTtheThomeT-TcorrectTanswer- dT(TheToutdoorTairTtemperatureTatTwhichTtheToutputTofTtheTheatTpumpTequalsTtheTheatTl ossTofTtheThome) WhatTvoltageTisTmeasuredTbetweenTanyTtwoTlegsTofTtheTthreeThotTlegsTinTaTdelta- connectedT240-VTthree-phaseTdistributionTpanel? a.T 208 TV b.T 240 TV c.T 277 TV d.T 380 TV SeeTpageT 107 T-TcorrectTanswer-bT(240TV)
WhichTofTtheTfollowingTstatementsTaboutTtheTinstallationTofTanTelectricTairTcleanerT(EAC )TisTtrue? a.TAnTEACTshouldTbeTwiredTsoTthatTitToperatesTonlyTwhenTtheTON/ OFFTswitchTisTinTtheT"ON"TpositionTandTtheTsupplyTairTblowerTisToperating b.TTheTcontrolTvoltageTsuppliedTtoTanTEACTcanTbeTasThighTasT5,000TV c.TTheTprimaryTfunctionTofTanTEACTisTodorTremoval d.TWhenTtheTrelativeThumidityTisTlow,TanTEACTshouldTbeToperatedTonlyTinTtheTheatingT modeT-TcorrectTanswer- aT(AnTEACTshouldTbeTwiredTsoTthatTitToperatesTonlyTwhenTtheTON/ OFFTswitchTisTinTtheT"ON"TpositionTandTtheTsupplyTairTblowerTisToperating) WhatTisTtheTindoorTairTflowTforTanTelectricTfurnaceTwhenTtheTsupplyTairTtemperatureTisT 9 8°F,TtheTreturnTairTtemperatureTisT70°F,TtheTvoltageTsuppliedTtoTtheTfurnaceTisT 220 TV,Ta ndTtheTcurrentTdrawTofTtheTfurnaceTisT 47 TA? a.T1,060TCFM b.T1,170TCFM c.T1,260TCFM d.T1,370TCFM Note:T CFMT=TBtuhT/T(1.08TxTTD) BtuhT=TWTxT3. WT=TVTxTAT-TcorrectTanswer-bT(1,170TCFM) WhichTofTtheTfollowingTstatementsTaboutTunderstandingTwiringTdiagramsTisTnotTtrue? a.TElectricityTalwaysTfollowsTtheTpathTofTleastTresistance b.TEveryTcircuitTmustThaveTaTloadTthatTconsumesTpowerTinTexchangeTforTwork c.TEveryTcircuitTmustThaveTaTpowerTsource d.TSchematicsTareTalwaysTshownTwithTtheTcircuitsTenergizedT-TcorrectTanswer- dT(SchematicsTareTalwaysTshownTwithTtheTcircuitsTenergized) SomeTtypesTofTloadsTmayTbeTconnectedTinTseries.TWhichTofTtheTfollowingTareTloadsTtha tTmustTnotTbeTconnectedTinTseries? a.TCapacitors b.THigh-pressureTswitches c.TMotors d.TResistiveTheaters SeeTpageT 116 T-TcorrectTanswer-cT(Motors) WhichTofTtheTfollowingTelectricalTcomponentsTisTaTpower-passingTdevice? a.TFanTmotor b.TFanTswitch c.TRelayTcoil
TheTuseTofTaTgroundTfaultTcircuitTinterrupterT(CFCI)TisTespeciallyTimportantTwhenT____. a.TapprenticeTworkersTareTaskedTtoTuseTpowerTtools b.TmoreTthanToneTelectricTtoolTisTpluggedTintoTanToutlet c.TtheTcordTofTanTelectricTtoolTisTfrayedTorTcracked d.TworkTisTbeingTdoneTonTwetTsurfacesT-TcorrectTanswer- dT(workTisTbeingTdoneTonTwetTsurfaces) AnTauto- rangingTmeterTautomaticallyTfindsTtheTbestTmeasurementTrangeTtoTdisplayTtheTquantity TofT____TbeingTmeasured. a.TamperesTorTohms b.TamperesTorTvolts c.TohmsTorTvolts d.Tamperes,Tohms,TvoltsT-TcorrectTanswer-dT(amperes,Tohms,Tvolts) WhatTANSITcategoryTisTbestTforTmetersTusedTinTHVACRTelectricalTwork,TandTwhy? a.TCATTI,TbecauseTmostTHVACRTelectricalTworkTisTdoneTonTcontrolTcircuits b.TCATTII,TbecauseTmostTHVACRTelectricalTworkTisTdoneTonTappliancesTthatTplugTintoT wallTreceptacles c.TCATTIII,TbecauseTmostTHVACRTelectricalTworkTisTdoneTonTappliancesTthatTareTperm anentlyTinstalled d.TCATTIV,TbecauseTmostTHVACRTelectricalTworkTisTdoneTonTutilityTconnectionsT- TcorrectTanswer- cT(CATTIII,TbecauseTmostTHVACRTelectricalTworkTisTdoneTonTappliancesTthatTareTperm anentlyTinstalled) WhatTcriticalTfirstTstepTmustTbeTtakenTtoTbeginTtheTtroubleshootingTprocess? a.TCheckTallTfusesTforTcontinuity b.TCheckTforTgroundedTmotorTwindings c.TCheckTrelayTandTcontactorThousingsTforTstuckTswitches d.TCheckTthatTtheTcorrectTvoltageTisTbeingTsuppliedTtoTtheTequipmentT-TcorrectTanswer- dT(CheckTthatTtheTcorrectTvoltageTisTbeingTsuppliedTtoTtheTequipment) ATgoodTfuseTwillTyieldTaTreadingTofT____TonTanTohmmeter. a.T 0 TΩ b.TlessTthanT 1 TΩ c.Tinfinity d.TaTvalueTthatTrisesTquicklyTtoT 0 TbeforeTfallingTslowlyTtowardTinfinityT-TcorrectTanswer- aT(0TΩ) WhichTofTtheTfollowingTlow- voltageTwiresTisTtypicallyTusedTtoTcarryTpowerTtoTtheTthermostatTsubbase? a.TGreen
b.TRed c.TWhite d.TYellowT-TcorrectTanswer-bT(Red) WhichTterminalTdesignationTonTtheTthermostatTsubbaseTtypicallyTisTusedTforTtheTcoolin gTcircuit? a.TG b.TR c.TW d.TYT-TcorrectTanswer-dT(Y) AnyTindividualTloadTinTaT24- VTcontrolTcircuitTshouldTdrawTaTmeasurableTcurrentTofT____TA. a.TlessTthanT 1 TA b.TbetweenT 1 TandT 2 TA c.TbetweenT 2 TandT 3 TA d.TmoreTthanT 3 TA SeeTpageT 151 T-TcorrectTanswer-aT(lessTthanT 1 TA) BlackTandTwhiteTleadsTonTaTstep-downTcontrolTtransformerTindicateTaT____. a.T24-VTacTsecondary b.T24-VTdcTsecondary c.T120-VTacTprimary d.T208-VTacTprimary SeeTpageT 155 T-TcorrectTanswer-cT(120-VTacTprimary) (Note: TypicalTcolorTcoding: 120 TV:TblackTandTwhiteTprimary,TyellowTandTblueTsecondary 230 TV:TredTandTblackTprimary,TyellowTandTblueTsecondary) ATresistanceTreadingTofT 0 TΩTacrossTaTcoilTindicatesTthatTtheTcoilTisT____. a.Tgood b.Tgrounded c.Topen d.TshortedT-TcorrectTanswer-dT(shorted) ATsmallTvoltageTreadingTacrossTaTclosedTsetTofTcontactsTinTanTenergizedTcircuitTindicat esTthatTtheT____. a.TcontactsTareTinTgoodTcondition b.TcontactsTareTpitted c.TmotorTcapacitorTisTdefective d.TwrongTvoltageTisTsuppliedTtoTtheTunitT-TcorrectTanswer-bT(contactsTareTpitted)
ExternalTstaticTpressureTisTtheTsumTofTtheT____TandTtheT____. a.TabsoluteTstaticTpressureTenteringTtheTairTfilter,TabsoluteTstaticTpressureTleavingTtheTa irTfilter b.TabsoluteTstaticTpressureTenteringTtheTindoorTblower,TabsoluteTstaticTpressureTleavin gTtheTindoorTblower c.TabsoluteTsupplyTstaticTpressure,TabsoluteTreturnTstaticTpressure d.TstaticTpressureTenteringTtheTevaporatorTcoil,TstaticTpressureTleavingTtheTevaporatorT coil SeeTpageT 172 T-TcorrectTanswer- cT(absoluteTsupplyTstaticTpressure,TabsoluteTreturnTstaticTpressure) WhatTisTtheToutputTofTaTresidentialTelectricTfurnaceTwhenTtheTvoltageTimpressedTisTequ alTtoT 235 TVTandTitsTcurrentTdrawTisT 40 TA? a.T10,150TBtuh b.T29,530TBtuh c.T32,080TBtuh d.T42,300TBtuh BtuhT=TWTxT3. WT=TVTxTA SeeTpageT 175 T-TcorrectTanswer-cT(32,080TBtuh) UseTtheTcollectedTserviceTdataTbelowTtoTcalculateTtheTairTflowTvolumeTforTaTresidentialT electricTfurnace: VoltageT=T 240 TVTac CurrentTdrawT=T 40 TA EnteringTairTtemperatureT=T70°F LeavingTairTtemperatureT=T105°F a.T 798 Tcfm b.T 867 Tcfm c,T 936 Tcfm d.T1,100Tcfm cfmT=T(voltageTxTcurrentTxT3.413)T/T(temperatureTriseTxT1.08)T-TcorrectTanswer- bT(867Tcfm) WhatTisTtheTmaximumTrecommendedTfaceTvelocityTforTairTleavingTaTsupplyTregister? a.T 300 Tft/min b.T 450 Tft/min c.T 500 Tft/min d.T 700 Tft/minT-TcorrectTanswer-dT(700Tft/min) TemperatureTreadingsTtakenTonTtheTrefrigerantTdischargeTlineT 6 Tin.TfromTtheTcompress orTmustTneverTexceedT____°F.
a.T150°F b.T175°F c.T200°F d.T225°FT-TcorrectTanswer-dT(225°F) WhatTproblemTresultsTwhenTtheTlimitTtemperatureTofTtheTdischargeTlineTatTtheTcompres sorTisTexceeded? a.TEvaporatorTsuperheatTwillTbeTexcessive,TcausingTcapacityTloss b.TGassingTofTtheTindoorTmeteringTdeviceTwillToccurTduringTtheTcoolingTcycle c.TSubcoolingTinTtheTcondenserTwillTdeclineTtoTaTdangerouslyTlowTlevel d.TTemperatureTinTtheTcompressorTwillTbeThighTenoughTtoTvaporizeTtheTlubricantT- TcorrectTanswer- dT(TemperatureTinTtheTcompressorTwillTbeThighTenoughTtoTvaporizeTtheTlubricant) ATsystemTshouldTbeToperatedTforTatTleastT____TbeforeTheatTmeasurementsTareTtaken. a.T 20 Tminutes b.T 30 Tminutes c.T 45 Tminutes d.T 1 ThourT-TcorrectTanswer-aT(20Tminutes) WhatTlevelTofTvacuumTisTneededTtoTensureTthatTaTsufficientlyTdeepTvacuumThasTbeenTd rawnTforTtheTremovalTofTwaterTvapor? a.T 500 Tmicrons b.T1,000Tmicrons c.T2,500Tmicrons d.T25,000TmicronsT-TcorrectTanswer-aT(500Tmicrons) WhatTpotentialTproblemTisTassociatedTwithTtheTuseTofTdyeTinjectedTforTtheTpurposeTofTle akTdetection? a.TDyeTcanTdamageTaTtechnician'sTrefrigerantTmanifoldTgauges b.TDyeTcanTincreaseTtheTpumpingTratioTofTtheTcompressor c.TOveruseTofTdyeTcanTchangeTtheTmixingTpropertiesTofTrefrigerantTandToil d.TOveruseTofTdueTcanTcreateTacidsTinTtheToil SeeTpageT 186 T-TcorrectTanswer- cT(OveruseTofTdyeTcanTchangeTtheTmixingTpropertiesTofTrefrigerantTandToil) WhatTgasTmustTbeTpurgedTthroughTaTrefrigerantTcircuitTtoTpreventTtheTformationTofToxid esTwheneverTbrazingTisTbeingTdone? a.TAnyTHFC b.TDryTnitrogen c.TFilteredTair d.TOxygenT-TcorrectTanswer-bT(DryTnitrogen)
