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• Section 608 of the Federal Air Act requires that all persons who maintain, service, repair, or dispose of appliances that contain regulated refrigerants, be certified in proper refrigerant handling techniques as of November 14, 1994.
There are 4 categories of technician certification:• TYPE I• TYPE II• TYPE III• UNIVERSAL
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Types• TypeI:Personswhomaintain,serviceorrepairsmallappliancesmustbecertifiedasTypeITechnician.
• TypeII:Personswhomaintain,service,repair,ordisposeofhigh-pressureappliances,exceptsmallappliancesandmotorvehicleairconditioningsystems,theymustbecertifiedasTypeIItechnicians.
• TYPEIII:Persons,whomaintain,serviceorrepairbothlowanhighpressureequipment,aswellassmallappliances,theymustbecertifiedasTypeIII.
• Universal:Persons,whomaintain,serviceorrepairbothlowandhighpressureequipment,aswellassmallappliances,mustbecertifiedasUniversalTechnicians.
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• Thetest containsfoursections.• Core,I,IIandIII• There are 25multiple-choicequestionsoneachsection.• Youmustscoreatleast70%or18outof25correctanswersoneachsectiontopass.
• Ifyoufailoneormoreofthesectionsonthetestyoumaytakearetest atalater datethetest willbeononlythesectionsyoufailedpreviously.
TESTFORMAT
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• IfyoupasstheCOREandonesectionyouwillbecertifiedinthattype.
• ForExample:IfyoupassthecoreandsectionIIyouwillgetacertificationforTYPEII,ButnotTYPEI,TYPEIIIorUNIVERSAL.
• TheCorecontains 25generalknowledgequestionsconcerningstratosphericozonedepletion,rulesandregulationsoftheCleanAirAct,theMontrealProtocol,refrigerantrecovery,recyclingandreclaiming,recoverydevices,substituterefrigerantsandoils,recoverytechniques,dehydration,recoverycylinders,safety,andshipping.
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• SECTIONIcontains25sector specificquestions pertaining tosmall appliances.
• SECTIONII contains25sectorspecificquestions pertaining tohigh- pressureappliances.
• SECTIONIII contains25sectorspecificquestions pertaining tolowpressureappliances.
• The testisaclosedbookexam.• Theonlymaterials thatmaybeallowedduring theexammaybeapressure/temp chartandacalculator.
• Bepreparedtopresentapicture ID,home addressandmakesureyoucheckwithyour localtestingcenteras towhatotherformsofidentification youmayneed.
• StudythesectionAor (CORE)and thesectionyouareseekingtogetcertified in.5
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CORE
• TheuseofCFC’sandHCFC’Shaschangedourlifestyles.Wedidnotrealizethetotaleffectsonourenvironment.Thegreatesteffectisonthestratosphere.
• Thestratosphereactslikeablanketthatsurroundstheearth.Itislocated10to30milesabovesealevelandiscomprisedof,amongotherthingsOzone.AnOzonemoleculeconsistsofthreeoxygenatoms.Ozoneprotectsusfromharmfulultravioletradiationandhelpsmaintainstabletemperatures.
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•Depletionoftheozoneinthestratospherecauses:• Increasesinskincancer• Lowercropyields• Increaseineyedisease• Reducedmarinelife• Deforestation• IncreasedgroundlevelOzone• UVraysare absorbedbytheozone• CFC’Slastupto50yearsintheAtmosphere• CFC’Shavebeenfoundinairsamplestakenfromtheatmosphere.• HFC’Sare harmlesstotheAtmosphere
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CORE
• CFC’SandHCFC’S,whenreleasedintotheatmospheredepletetheatmosphere.
• Theculpritinthesecompoundsisthechlorine.WhenachlorineatommeetswithaOzonemolecule,ittakesoneoxygenatomfromtheOzone.ThisformsacompoundcalledChlorineMonoxide(CIO)andleavesanO2 molecule.TheChlorineMonoxidewillcollidewithanotherOzoneMolecule,releaseitsoxygenatom,formingtwoO2 molecules,andleavethechlorinefreetoattackanotherOzonemolecule.
• AsingleChlorineatomcandestroy100,000OzoneMolecules.
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• TherehasbeenalotofcontroversyoverthesubjectofOzoneDepletion.Somefolksbelievethatthechlorinefoundinthestratospherecomesfromnaturalsourcesasvolcaniceruptions.HoweversamplestakenduringaneruptionareveryminimalascomparedtoCFC’s.
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• Inaddition, the riseintheamountofchlorinemeasured inthestratosphereover thepast2decadesmatches therise intheamountofFluorine,whichhasdifferentnatural sourcesthanchlorine,over thesame period.
• Alsothe riseintheamountofchlorinemeasured inthestratosphereover thepasttwentyyears,matches therise inCFCemissionsover thesametimeperiod.
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•Unlikeotherchlorinecompoundsandnaturallyoccurringchlorineintheatmosphere.
•CFC’Swillneitherdissolveinwaternorbreakdownintocompoundsthatdissolveinwater,sotheydonotrainoutoftheatmosphere….
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CORE• OZONEDEPLETIONPOTENTIAL• OzoneDepletionPotential (ODP)isameasurementofCFC’S andHCFC’Sability todestroy theozone.CFC’Shavethehighestpotential ODP.• HFC’S(134-A)donotcontainchlorineandhavenoOzoneDepletionPotential.
TYPE EXAMPLE ELEMENTS
CFC
HCFC
HFC
R-11, 12, 500
R-22, 123
R-134-a, 410a
Chlorine Fluorine Carbon
Hydrogen Chlorine Fluorine Carbon
Hydrogen Fluorine Carbon
VERY IMPORTANT1 2
CORE & CLEAN AIR ACT
• TheUnitedStates EnvironmentalProtectionAgency(EPA)regulatessection608oftheFederalCleanAirAct.
• Failuretocomplycouldcostyouasmuchas$27,000perday,perviolationandthereisabountyof$10,000tolureyourcompetitors,customersandfellowworkerstoturnyouin.
• Service TechnicianswhoviolatetheCleanAirActmaybefined,losetheircertification,andhavetoappearinfederalcourt.
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• The EPA may require a technician todemonstrate the ability toproperly perform refrigerant recovery/recycling procedures.
• Failingtodemonstrate these skillsmayresult inevocation ofcertification.
• Itisaviolation ofsection608TO:• Falsify orfailtokeep required records• Failtoreach required evacuation rates prior toopeningordisposingofappliances.
• Knowinglyrelease (VENT) CFC’S,HCFC’S orHFC’S while repairingappliances,withthe exception ofDE-MINIMUS releases
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• Service, maintain,ordisposeofappliancesdesignedtocontainrefrigerants withoutbeingappropriatelycertifiedasofNovember14,1994.
• Itistheresponsibilityofthefinalpersoninthedisposalchaintoensurethatrefrigerant hasbeenremovedfromtheappliancesbeforescrapping.
• FailtorecoverCFC’S,HCFC’S,beforeopeningordisposingofanappliance.
• FailtohaveanEPAapprovedrecoverydevice,equippedwithlowlossfittings,andregisterthedevicewiththeEPA.
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• Addnitrogentoafullychargedsystem,forthepurposeofleakdetection,andtherebycauseareleaseofthemixture.
• Disposeof adisposablecylinderwithoutfirstrecoveringanyremainingrefrigerantto0psig.andthenrenderingthecylinderuseless,thenrecyclingthemetal.
• Inaddition,somestateandlocalgovernmentregulationsthatareasstrictorstricterthanSection608.
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CORE / MONTREALPROTOCOL
•Followingseveralyearsofnegotiations,aninternationalagreement(TREATY)regulatingtheproductionanduseofCFC’S,HCFC’S,halons,methylchloroform andcarbontetrachlorideenteredintoforceinmid1989.
•KnownasTHEMONTREALPROTOCOL, thislandmarkagreementinitiallyrequiredtheproductionandconsumptionfreeze.
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•TheMontrealProtocolcalledforastepwisereductionandeventualproductionphaseoutofvariousOzoneDepletingSubstancesindevelopedCountries.
CFC’Swerephasedoutofproduction December31,1995.
•HCFC,Srefrigerantsarescheduledofphaseoutinthefuture.
•WhenvirginsuppliesofCFC’Saredepleted,futuresupplieswillcome fromrecovered,recycled,orreclaimedrefrigerants.
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Recovery, Recycle & ReclaimTHETHREE“R,s”
Recover,RecycleandReclaim
• ToRECOVER is to removerefrigerantinanycondition fromasystemandstore it inaexternalcontainer (recoverybottle-gold topandgraybottom.)
• To RECYCLE is tocleanrefrigerantfor reusebyseparatingtheoil fromthe refrigerantand removingmoisture fromthe refrigerantbypassing itthroughoneormore filterdries.
• ToRECLAIMis toprocess refrigeranttoa levelequal toanew (VIRGIN)productspecificationsasdeterminedbychemicalanalysis. RECLAMEDrefrigerantmustmeetthestandardset forthinARI700before itcanbe resold.
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RECOVERYDEVICES
• Refrigerant Recovery and/orRecyclingequipmentmanufacturedafterNovember15,1993,mustbecertifiedandlabeledbyanEPAapprovedequipmenttestingorganizationtomeetEPAStandards.
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• 1“SystemDependent”whichcapturesrefrigerantwiththeassistanceofcomponentsintheappliancefromwhichrefrigerantisbeingrecovered.
• 2 “Self-Contained”whichhasitsownmeanstodrawtherefrigerantoutoftheappliance.
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2 ways to recover
• AsofNovember14,1994,thesaleofCFCand HCFC refrigerantsisrestrictedtocertifiedtechnicians.OnlytechnicianscertifiedundertheCleanAirAct Section608areallowedtopurchaseorhandle refrigerants.
(MotorVehicleairConditioning)areallowedtopurchaserefrigerantsincontainerssmallerthan20lbs.
SALES RESTRICTIONS
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Substitute Refrigerants and Oils
• Overthepastseveralyears severalnewrefrigerants, blendsanddifferentoilshavebeendevelopedforrefrigeration.
• R-134aisanozonefriendlyrefrigerantanditistheleadingreplacementrefrigerantforR-12butitisnotadropinrefrigerant.
• There isno dropinrefrigerantforR-12,but134acanbeusedinmostR-12systemsifyoufollowtheproperretrofitprocedures.
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Things to remember about 134a
• R-134awillnotmixwithmostrefrigerants.• TheoilusedinmostR-134asystemsareEASTERS.
• Easterscannotbemixedwithotheroils.
• Itisveryimportantthatwhenyouleaktesta134asystemtousepressurizednitrogen.
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SubstituteRefrigerantsandOils• There are severalblendsofrefrigerantinusetoday.Someoftheblendsare calledTernary,whichmeanstheyareathree-partblend.Ternaryblendsusealkylbenzeneforitslubricant.
• Youneedtomakeabsolutelysuretousethecorrectlubricantfortherefrigerant.
• Mostrefrigerant oilsare hygroscopic.• Hygroscopicoilshaveahighaffinityforwater.• Oilsamplesshouldbetakenandtestediftherehasbeenamajorcomponentfailure.
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•1Thecomponents ofblended refrigerantwillleakatdifferentratesbecauseofhavingdifferentvaporpressures.
•2Thepropermethodforchargingablendedrefrigerantistoweighinthechargethroughtheliquidserviceportonthehighside.
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About Blends
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• Atermyouneedtorememberis“temperatureglide”• Temperatureglidereferstoarefrigerantblendthathasarangeofboilingpointsorcondensingpointsthroughouttheevaporatorandthecondenserrespectively.
• OTHERblendsmaybeazeotropic,meaningthatitisblendedbutitactslikeasinglecomponentrefrigerantoveritsentiretemperature/pressurerange.
• Aazeotrope doesnothaveatemperatureglide.
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About Blends
Recovery Techniques
• Service rates haveincreasedsincerecoverywasmademandatory.
• EPAregulationsrequireaserviceaperture orprocessstubonallappliancesthatuseaClassIorClassIIrefrigerantinordertomakerecovery easier.
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Recovery Techniques
• Whenrecoveringrefrigerant, nevermixtwodifferentrefrigerants intothesamerecovery cylinder.Whenservicingaunitandyoudiscoverthat twoormorerefrigerantshavebeenmixedwithintheunit,youmustuseaseparatetank,becausetherefrigerantmaynotbeabletobereclaimed.
• Recoveronlyonetypeofrefrigerantintoarecoverycylinder.
• Ifyousmellastrongodorduringtherecoveryprocess,acompressorburn-outhaslikelyoccurred.Whenrecoveringaburn-outunit,checkforcontaminationintheoil.
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• Afteryourecovertherefrigerant,andyouusenitrogen toflushout thedebris fromthesystem, it is legal foryoutoventthenitrogen.
• Itisagood ideato install asuction line filterdrier tocatchanydebristhatmaybestillin thesystem inorder toprotectthenewcompressor.
• The lengthofhosebetween therecoverymachineandgaugeswill greatlyaffecttheefficiencyoftheprocess.Longerhoseswill causeapressure drop,andgreatlyincrease therecoverytimeandhaveagreaterchanceofincreasedemissions.Sinceall refrigerantshaveapressure temperaturerelation, thelower theambienttemperature, theslower therecoveryrate.Afteryou finish recoveringall liquidrefrigerant,youshould guardagainst trapping liquid betweentheservicevalves.
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RecoveringRefrigerant
• Recovery machineisjustacompressorPumpsvaporonly
• Inletisthesuctionsideofcompressor
• Outletgoestorecoverytank
• Recovery tankactsasacondenser
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VaporRecovery
© 2 0 1 2 Refrigeration Train in gServices -R1 Sub ject5 Recoveryv2 3 2
Vapor Recovery
Fi l ter DrierSigh t GlassReceiver
EVAPORATOR
CONDENSER
GaugeMan i fo ld
Comp resso r
TEV
RecoveryC yl in der
Scale
Openvalve
Start recovery
Nowopenhighsidegauge valve
Refrigerantnowintank
RecoveryUn it
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RecoveryCompleted
© 2 0 1 2 Refrigeration Train in gServices -R1 Sub ject5 Recoveryv2 3 3
Fi l ter DrierSigh t GlassReceiver
EVAPORATOR
CONDENSERComp resso r
TEV
RecoveryC yl in der
Scale
RecoveryUn it
Allrefrigerantisrecovered whenunitpullsavacuum
GaugeMan i fo ld
System nowreadyforremoval, repair,etc.
“Push-Pull”LiquidRecovery
• Large unitshavealotofrefrigerant• Vaporrecoverytakes toolong• Recovery unitcanpush liquidintotank
Thenpull out remainingvapor
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© 2 0 1 2 Refrigeration Train in gServices -R1 Sub ject5 Recoveryv2 3 5
LiquidRefrigerantRecovery:"Push-Pull"Method
Fi l ter DrierSigh t GlassReceiver
EVAPORATOR
CONDENSERComp resso r
TEV
RecoveryC yl in der
Scale
RecoveryUn it
GaugeMan i fo ld1 - Openhighsidegauge valve2- Openbothrecoverytankvalves3- Frontseatkingvalve
4- Turnonrecoveryunit,pushliquidoutof condenserandreceiver intorecoverytank
5- Mostof theliquidhasnowbeenremoved. Beginvaporrecovery (shownpreviously) .
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EvacuatedTankLiquidRecovery
• Pullavacuumonarecoverytank• Connecttoreceiver• Thetankwillsuckoutliquid• Note:acoldtankwillspeedthetransfer
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RecoverytankinaVacuum
Liquid Recovery: Evacuated Tank
Compre sso r
Filte r-Drie rSigh tGlass Re ce ive r
Scale s
Gauge Man ifo ld
Front seatKingValve
Userecovery unit to completevapor removal
EVAPORATOR
CONDENSER
Liquid refrigerant canberemoved without arecoverymachine
Vacuum intankremoves most ofthe liquid
Liquid is suckedout
TEV
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DEHYDRATION
• Properdehydrationproceduresthroughevacuationareimportanttofollow.
• Thereasonfordehydrationistoremovewatervaporandwater.• Ifleftinarefrigerationsystem,moisturewillformhydrochloricandhydrofluoricacids.
• Evacuationisthesuggestedmethodfordehydration.• Itisnotpossibletooverevacuateasystem• Never evacuate asystemtotheoutsideairbeforeyourecoverthesystemfirsttothemandatedvacuumlevel.
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• Herearesomethingsthateffectthespeedandefficiencyofevacuation:• 1sizeofequipment• 2ambienttemperature• 3amountofmoistureinthesystem• 4&5thesizeofthevacuumpumpandsizeofthesuctionline• 6thesizeofthevacuumlineshouldbethesamesizeorgreaterthanthesizeofthepumpintakefitting.
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• Thesystemvacuumgaugeshouldbelocatedasfarawayfromthevacuumgaugeaspossible.
• Thevacuumreadingshouldbetakenwhenthesystemisisolatedandthevacuumpumpisturnedoff.
• Ifthesystemdoesn’tholdavacuum,thenthereisprobablyaleak.
• Duringevacuationyoumaywanttoheattherefrigerationsystemtospeedupdehydration.Ifthesystemholdstherequiredvacuum,yourfinished.
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SingleEvacuation
• Whatisevacuation?Pulling avacuumonasystem
• Why?Toremoveairandmoisture
• Howlong doyouevacuate?Longenough togetto500microns
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EvacuateGaugeHoses
© 2 0 1 2 Refrigeration Train in gServices -R1 Sub ject6 LeakCheckand Evacuation v2
4 2Filter DrierSight
G lassReceiver
EVAPORATOR
CONDENSER
Compressor
TEV
Gauge Manifold
Vacuum Pump
500
RECOVERY CYLINDERS
• Recovery cylindersdifferinmanywaysfromdisposablecylinders.DisposablecylindersareusedonlywithvirginrefrigerantandmayNEVER beusedforrecovery.
• Recovery cylindersarespeciallymadetoberefilled.
• Recovery cylindershave2ports,oneliquidand one vapor.
• Extreme care mustbetakenwhenfillingthecontainers,soastonotcauseanexplosion.
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• TheEPArequiresthat arefillablerefrigerant
• Refillablecylindersusedfortransportingrecoveredpressurizedrefrigerant mustbeDOTapproved.ApprovedrefrigerantrecoverycylindersshouldbeinspectedforRUST.
• Iftheyshowsignsofrustorappearnottobesecuretheyshouldbereducedto0psiganddiscarded.
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DisposableRefrigerantDrums
Lookfordirectionondrum:Uprightposition, chargewithvaporUpsidedown, chargewith liquid
SomemanufacturerstrieddiptubesItis confusing,most stopped
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Freon tanks
Originally R404Atanks had diptubes
R22 tank cut-a-wayview
Now R404A tanks have NOdiptubes
Turn over forliquid
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SAFTY
• Whenhandlingand filling refrigerantcylinders,oroperating recoveryequipmentorrecyclingequipment, youshould wearsafetyglasses, protectivegloves,and followallequipmentmanufacturerssafetyprecautions.• Whenpressurizing asystemwith nitrogen,youshould alwayschargethroughapressure regulatorand install apressure reliefvalvein thedownstream line fromthepressure regulator.• RELIEFVALVESMUSTNOTBEINSTALLEDINSERIES.• Ifcorrosion is foundwithin thebodyof thevalve, thevalvemustbereplaced.• When leakcheckingasystem,NEVER pressurize itwith compressedair.• Whenmixedwith refrigerants,oxygenorcompressedair cancauseanexplosion.
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• NEVERHEAT AREFRIGERANT CYLINDERWITHAOPENFLAME.
• Donotcutorbrazerefrigerantlinesonachargedunit.
• Intheeventofalargerelease ofrefrigerant inaconfinedspace,SelfContainedBreathingApparatus(SCUBA)isrequired.Ifalargeleakofrefrigerant occursinanenclosedarea,andSCUBAisnotavailable,IMMEDIATELY VACATEANDVENTILATE thearea.
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• Todeterminethesafeworkingpressureofasystem,checkthedataplateforthelow-sidetestpressurevalue.
• Whenusinganyequipmentthatusesschrader valves,checkforleaks,bendsandbreakage.
• Replacedamagedschrader valvecorestopreventleakage,andalwayscapschrader portstopreventaccidentaldepressionofthevalvecore.
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SAFTY
• Inlargequantities,refrigeantscancausesuffocationbecausetheyareheavier thanairanddisplaceoxygen.
• Inhalingrefrigerantvaporsormistmaycauseheartirregularities,unconsciousness,andoxygendeprivationleadingtodeath.
• NeverexposeR-12orR-22toopenflamesorglowinghotmetalsurfaces.Athightemperatures,R-12and R-22decomposetoformHydrochloricacid,Hydrofluoricacid,andPhosgenegas.
• Alwaysreviewthesafetydata sheets,whenworkingwithsolvents,chemicalsorrefrigerants.
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SHIPPING & TRANSPORTING
•Beforeshipping anyused refrigerantcylinders, checkthatthecylindermeetsDOTstandards, completetheshipping paperwork including thenumberofcylindersofeachrefrigerant,andproperly label thecylinderwith the typeandamountofrefrigerant.
• Cylinders should betransported inanuprightposition.
• EachcylindermustbemarkedwithaDOTclassification tagindicating it isa“2.2non-flammablegas”.
• Somestatesmayrequirespecial shipping procedures tobefollowed basedon theirclassificationof used refrigerants.
• Checkwith theDOTinyourstate.
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• EndofCorePrepcourse.
• Please download the PDF’s review the information and review the video, study and good luck on the test.
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