HVAC REFRIGERATION FINAL EXAM QUESTIONS WITH ANSWERS.

HVAC REFRIGERATION FINAL EXAM
QUESTIONS WITH ANSWERS
TheTlocked-rotorTamperageTisTnormallyT____TtimesTasTgreatTasTtheTrun-loadTamperageT-
TCORRECTTANSWERS-Five




WhenTaTcontactor'sTcoilTisTenergized,TvoltageTshouldTbeTmeasuredTbetweenTterminalT"Li"TandTter
minalT"TI"?T-TCORRECTTANSWERS-"0"TVolts



TechnicianT"A"TsaysTthatTifTyouTtakeTaTvoltageTreadingTfromTterminalT"Li"TtoTterminalT"TI"TonTaTcont
actorTwhoseTcoilTisTenergized,TyouTshouldTreadTzeroTvolts.TTechnicianT"B"TsaysTthatTcontactorsTcanT
onlyThaveTnormallyTopenTcontacts.TWhichTofTtheTfollowingTstatementsTisTcorrect?T-
TCORRECTTANSWERS-TechnicianT"A"TisTcorrect.TTechnicianT"B"TisTincorrect




ATtechnicianTneedsTtoTcheckTaTsingle-
phaseTcompressor.THeTlabelsTtheTthreeTterminalsT"A,""B."TandT"C"TandTtakesTresistanceTreadingsTo
fTtheTwindings.THeTreadsT10TohmsTfromT"A"TtoT"B."TinfinityTfromT'B"TtoT"C."TandTinfinityTfromT'C"TtoT
"A."TIdentifyTtheTterminals.T-TCORRECTTANSWERS-CannotTidentifyTterminals:TopenTwinding



TechnicianT"A"TsaysTthatTwhileTcheckingTtheTwindingsTofTaTcompressor,TaTreadingTofT10TohmsTorTle
ssTfromTtheTcommonTterminalTtoTgroundTindicatesTthatTtheTmotorTisTokay.TTechnicianT"B*TsaysTtha
tTtheTresistanceTofTtheTstartTwindingTshouldTalwaysTbeTlessTthanTtheTresistanceTofTtheTrunTwinding.
TWhichTofTtheTfollowingTstatementsTisTcorrect?T-TCORRECTTANSWERS-


TechnicianT"A"TisTincorrect.TTechnicianT"B"TisTincorrect.



AnTopenTwindingTinTanTeiectricTmotorTmeansTthatT____T-TCORRECTTANSWERS-
ATwireTinTaTwindingTisTbroken



TecnnicianT"A"TsaysTthatTaTshortedTwindingTwillTresultTinTanTincreasedTcurrentTflowTthroughTtheTwi
nding.

, TechnicianT"B"TsaysTthatTifTaTmotorTisTtoTbeTreplaced,TaTmotorTwithTaTlowerThorsepowerTratingTsho
uldTalwaysTbeTused.TWhichTofTtheTfollowingTstatementsTisTcorrect?T-TCORRECTTANSWERS-
TechnicianT"A"TisTcorrect.TTechnicianT"B"TisTincorrect.



IfTaTcondenserTfanTmotorTgroundsTout.TitTwillTusually____T-TCORRECTTANSWERS-
TripTaTcircuitTbreakerTtoTshutToffTtheTunit



IfTaTmotorThumsTbutTdoesTnotTstart,TthereTisTaTpotentialTproblemT-TCORRECTTANSWERS-
allTofTtheTaboveT(withTtheTstartingTcomponents,TwithTanTopenTwinding,TwithTinsufficientTsupplyTvol
tage)



ATtypicalTevaporatorToperatingTtemperatureTinTanTair-conditioningTsystemTisTabout____T-
TCORRECTTANSWERS-40TF




TheT______TofTtheTliquidTrefrigerantTdeterminesTtheTcoilToperatingTtemperature.T-
TCORRECTTANSWERS-boilingTtemperature




ATtypicalTsuperheatTforTanTevaporatorToperatingTunderTnormalTconditionsTwouldTbeT-
TCORRECTTANSWERS-8TtoT12°F




ATnormallyToperatingTwater-
cooledTcondenserTisToperatingTwithTaT10°TdifferentialTbetweenTwaterTinTandTwaterTout.TIfTscaleTfor
msTonTtheTwaterTtubesTandTtheTenteringTwaterTisT85°F,TwhichTofTtheTfollowingTisTpossible?T-
TCORRECTTANSWERS-


BothTATandTBTareTcorrectT(TheToutletTwaterTtemperatureTwillTbeTlowerTthanTexpectedTANDTTheTsys
temTheadTpressureTwillTrise)



MineralTdepositsTinTtheTwaterTportionTofTaTwater-cooledTcondenserTactTasT-TCORRECTTANSWERS-
anTinsulator