HVAC Excellence Questions and Answers 2025 Guaranteed Pass

HVAC Excellence Questions and Answers
2025 Guaranteed Pass
HeatAwhichAcausesAaAchangeAinAtemperatureAofAaAsubstanceAisAcalled.A-
ACORRECTAANSWERSA-sensibleAheat.

HeatAaddedAtoAaAsubstanceAwithoutAaAriseAinAtemperature;A(example:AliquidArefrigerantAtoA
gas)AthisAprocessAisAcalled?A-ACORRECTAANSWERSA-LatentAheat
HeatAaddedAtoAtheArefrigerantAinAaAvaporAstateAafterAtheAevaporatorAprocessAisAcalled.A-
ACORRECTAANSWERSA-Superheat

AAscrollAcompressorAmovesArefrigerantAbyAmeansAof.A-ACORRECTAANSWERSA-
InvoluteAspirals
TheAmovementAofAheatAbyAwayAofAfluidAorAisAcalledAairAorAgas.A-ACORRECTAANSWERSA-
Convection
TheAmovementAofAheatAthroughAaAsolidAobjectAisAcalled.A-ACORRECTAANSWERSA-
Conduction
TheAstandardAunitAforAmeasuringAtheAQUANTITYAofAheatAinAaAsubstanceAisA(intensityAwoul
dAbeAtemp)A-ACORRECTAANSWERSA-BritishAthermalAunit
AArefrigerantAgivesAupAheatAwhenAit.A-ACORRECTAANSWERSA-ItAcondenses
WhyAmustArefrigerantAinAtheAsuctionAlineAbeAslightlyAwarmerAthanAtheAsaturationAtemperatu
re?A-ACORRECTAANSWERSA-PreventAliquidAsluggingAofAtheAcompressor
ItAisAdesirableAforArefrigerantAinAtheAsuctionAlineAtoAbeAslightlyAsuperheatedAinAorderAto.A-
ACORRECTAANSWERSA-InsureAliquidArefrigerantAdoesAnotAenterAtheAcompressor

TheAstateAofAtheArefrigerantsAinAtheAsuctionAlineAshouldAbe.A-ACORRECTAANSWERSA-
LowApressureA/ALowAtemperatureAvapor
TheAstateAofAtheArefrigerantAenteringAtheAcondenserAis.A-ACORRECTAANSWERSA-
HighApressureA/AHighlyAsuperheatedAvapor
TheAevaporator.A-ACORRECTAANSWERSA-
TransfersAheatAfromAtheArefrigeratedAspaceAtoAtheArefrigerant
WhichAofAtheAfollowingAisAnotAaAthermodynamicApropertyAofArefrigerant.A-
ACORRECTAANSWERSA-Flammability

TheAsequentialAorderAofAstepsonAtheAvapor-compressionAprocessAare.A-
ACORRECTAANSWERSA-Compression,Acondensation,Aexpansion,Avaporization

IfAaA30ApoundAcontainerAofAR-
410AArefrigerantAhasAbeenAstoredAoverAnightAatA70'F,AtheApressureAinAtheAcylinderAshouldA
beAapproximately.A-ACORRECTAANSWERSA-201Apsig
FanAairflowApressuresAareAusuallyAmeasuredAin.A-ACORRECTAANSWERSA-
InchesAofAwaterAcolumnA(WC)
ZeroApsiaA(poundsAperAsquareAinchAabsolute)Ais.A-ACORRECTAANSWERSA-
AApressureAwhichAcannotAbeAfurtherAreduced
ZeroApsigA(ApoundsAperAsquareAinchAgauge)Ais.A-ACORRECTAANSWERSA-
TheAsameAasAatmosphericApressure
TheAtemperatureAatAwhichAmoistureAwillAstartAtoAcondenseAfromAtheAairAisAcalled.A-
ACORRECTAANSWERSA-DewApointAtemperature

, AAcompoundApressureAgaugeAmeasuresA-ACORRECTAANSWERSA-
PressureAandAvacuum
AAmechanicalAshaftAsealAisAnecessaryAonAaA-ACORRECTAANSWERSA-
OpenAdriveAcompressorA/AexternalAforce
LiquidAsluggingAis.A-ACORRECTAANSWERSA-
LiquidArefrigerantAinAtheAcompressorAclearanceAspace
TheAclearanceAspaceAinAaAreciprocatingAcompressor.A-ACORRECTAANSWERSA-
HasAnoAeffectAonAcompressorAcapacity
WhichAofAtheAfollowingAtypesAofAairAconditioningAcompressorsAisAmostAenergyAefficientA-
ACORRECTAANSWERSA-CentrifugalA(ABTU/KiloAwattsA)

WhichAofAtheAfollowingArepresentsAtheArightAorderAforAtheAfunctionsAofAaAcondenser.A-
ACORRECTAANSWERSA-De-superheatsA,AcondensesA,Asub-cools

RefrigerantAR-
134aAvaporAentersAtheAcondenserAatA124Apsig,A100'F.AItAleavesAasAaAliquidAfromAtheAconde
nserAsub-cooledA20'F,AandAtheApressureAwillAbeAapproximately.A-ACORRECTAANSWERSA-
124Apsig
ThereAareAthreeAbasicAtypesAofAcondensers,AtheAairAcooled,AtheAwaterAcooledAandAtheABLA
NKAcooled.A-ACORRECTAANSWERSA-Evaporative
10lbs.AOfArefrigerantApassingAthroughAaAwaterAcooledAcondenserAwillAloseA20ABTUAofAheat
AperAlb.AifA10lbs.AOfAwaterApassesAthroughAtheAcondenserAwithAanAenteringAtemperatureAofA

80'F.ATheAtemperatureAofAtheAwaterAleavingAtheAcondenserAis.A-ACORRECTAANSWERSA-
100'F
TheAheatAremovedAfromAtheArefrigerantAbyAtheAcondenserAis.A-ACORRECTAANSWERSA-
BothAsensibleAandAlatentAheat
AnAenergyArecoveryAventilatorAis.A-ACORRECTAANSWERSA-
AnAairAtoAairAheatAexchangerAtoArecoverAheat
WhichAofAtheAfollowingAcanANOTAbeAusedAasAaAlowAambientAtemperatureAcontrol?A-
ACORRECTAANSWERSA-CrankcaseAregulatingAvalves

WhenAtestingAtheAefficiencyAofAanAairAcooledAcondenser,AtheArefrigerantAcondensingAtemp
eratureAshouldAbeAnoAmoreAthanA___________AhigherAthanAtheAenteringAairAtemperature.A
-ACORRECTAANSWERSA-30'F
WhenAtestingAefficiencyAofAaAwaterAcooledAcondenser,AtheArefrigerantAcondensingAtemper
atureAshouldAbeAapproximatelyA_________________AhigherAthanAtheAleavingAwaterAtemp
erature.A-ACORRECTAANSWERSA-10'F
TheAfirstAfunctionAaAcondenserAmustAperformAisAtoA____________AtheArefrigerantAbeforeAc
ondensingAcanAoccur.A-ACORRECTAANSWERSA-De-superheat
AAthermostaticAexpansionAvalveAisAdesignedAtoAmaintain.A-ACORRECTAANSWERSA-
ConstantAevaporatorAsuperheat
TheAthermostaticAexpansionAvalveAhasAthreeAoperatingApressure.A-
ACORRECTAANSWERSA-EvaporatorApressure,AspringApressureA&AsensingAbulbApressure.

WhenAmountingAaAthermostaticAexpansionAvalveAsensorAbulb,AwhichAofAtheAfollowingAisAN
OTAtrue?A-ACORRECTAANSWERSA-ItAmustAbeAinstalledAlowerAthanAtheAvalveAbody
InAanAairAconditioningAsystemAthatAusesAaAthermostaticAexpansionAvalve,AtheAtemperatureA
ofAtheAevaporatorAoutletAwillAusuallyAbe.A-ACORRECTAANSWERSA-
WarmerAthanAtheAevaporatorAinlet