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Certification Training Manual - Mac`s

1. Ih 39 PUD OF NeW IS ESERE EE ERP a UE PEDEM UNES 39 Recovering Refrigerant from Disposable Cylinders 2 40 Field Coupling of Flexible Hose Assemblies 41 Practical MOUSES E MER KC ede pde s aded nd oo don dou don ES 41 Measure Twice Crimp Once US Ner E RUE HORSE E P dtr PIER 41 Appearance lt ed er te le meteo en 42 Replacement Refrigerants and Retrofitting Mobile A C Systems 42 What About Retrofitting 134 Systems ict bee ERROR EORR OU RO ERROR URGE errors 42 The U S Significant New Alternative Policy SNAP 42 A Word on Flammable Refrigerants dax Pad ev eU our 45 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE NM 5 Servicing of Future Mobile Air Conditioning Systems 46 European Phase out of HFC 134 srrissisrisiasss sistat a a a TEE b E 46 R744 Carbon Dioxide Systems oro asec pr Debo sess PSU EE PLE ba dt 46 T5238 SNS OS ed ues oru PPS I EPIIT EPUM a PR RUPEE EPA 46 Other Alternative 1 lt EE PPP UE IEEE ce PPP GU CPUN 46 SAETSVIAGCPEOG
2. ce ce 1 More on Ozone 1 2 CFCs and their Affect OZONE td eus ae ed ERU de CR DO Re 2 Health and ERMIO MSN IA LEA a a 3 Human ELLE OL PE ES CIF EO 3 Plantand Marine essen tnit rnar EMO RUN EDI PED PU Kao e dudes 4 OUYVSF WIND UE 4 Global Problem S n ERO SR CR RR RU 3 a t n OR ad 4 GOLOC OMe ater arp cas eder en edes ador dd adit ae dad dard ed duode ier dde vada ed dc dodo 4 VER E PA TRU 4 Cree RuCl eae ee ee ee ee ee ee ee ee ee eee ee ee ee ee 4 Field Study Refrigerant Recovery and Reuse nns 5 The Switch to HFC T34a Refrigerant nee did ne css OEC E EE E ERE EHE CER OEC 5 Federal Regulations Affecting Mobile A C System 6 Equipment Use a eene hh 6 Technician Training and Certification Requirements lesse he 6 Overlap Between Sections 608 and 609 of the Clean Air 6 Mobile A C Service Equipment Certification Operation and Refrigerant Purity 7 More Complete Refrigerant Recovery ep a haven CEA eC E e AO ER eA HE eb s 8 dies oia e UM 8 Purity OF R
3. 5 28 Show the Data SET AS FERS SERS CEDE ie 28 CA E E A E N A A 28 Incorrect System Charges Some Reasons Why 31 Making an Unintentional Mistake While Determining the Charge Amount 31 Incomectcadleuiation Ol C Sl OB oar 31 EQUIOMenLIMACCUNACY LLL TOLLIT 33 Test Procedure for Refrigerant Transfer eh s 34 Not Accounting for the Refrigerant inside the Service 34 Technician Doesn t Accept the 5 hm 34 Charging Systems with Small Cans or by Attempting to Use Pressure Readings 34 More on Refrigerants and the Proper Use of Refrigerants 35 Three Questions on Air contaminated 29 Mixed Cross contaminated Refrigerant cece sis ses 37 Two More Issues Concerning Refrigerant and System Contamination 39 Recovery and Disposal of Contaminated Refrigerant 39 Used Refrigerant from Non mobile Sources
4. Ozone Molecule In the upper atmosphere ultraviolet light breaks off a chlorine atom from a chlorofluorocarbon molecule The chlorine attacks an ozone molecule breaking it apart An ordinary oxygen molecule and a molecule of chlorine monoxide are formed break down until they are carried by wind currents into the stratosphere a process that can take as long as 10 years In the stratosphere these chemicals absorb UV radiation break apart and react with ozone taking away one oxy gen atom and forming chlorine monoxide Chlorine mon oxide further breaks down ozone by pulling away a single oxygen atom creating two oxygen molecules Once freed the chlorine acts as a catalyst repeatedly combining with and breaking apart ozone molecules It is believed that one CFC molecule can destroy as many as 100 000 ozone molecules CFC s ozone degrading effect became more evident with the discovery of the Antarctic Ozone Hole British research New oxygen Chlorine monoxide Free Oxygen Atom Mon M T Oxygen molecule former Chlorine Ozone Molecule monoxide molecule A free oxygen atom breaks up the chlorine monoxide molecule The chlorine atom is then free to repeat the process Chlorine atoms from CFCs break apart ozone molecules This results in a reduction of stratospheric ozone 2 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE This shows how ozone depletion has resulted in an ozone hole located
5. Outside air not max e High fan speed e Airflow panel outlets ATC Systems Set temperature mid range O Checkto make sure system is on outside air drawing air from vehicle cowl air inlet area 2 Vehicle hood open to allow warm engine air to en ter cowl inlet to A C system lt Operate engine idle condition Neutral park with parking brake applied e Depending upon engine compartment temperature O Run engine to warm up A C system com ponents for 15 minutes After idling engine for 15 minutes hot condition Stop engine and then turn ignition to on position allowing operation of O A Cfan high system on Outside air When applicable Operation of electric engine cooling fan to circulate air in en gine compartment Do not change any control or conditions listed in steps 1 and 2 above O Start refrigerant recovery process gt When refrigerant recovery is completed in cluding the required 5 minute recheck for system pressure system refrigerant out gas sing shut vehicle and equipment off To recover as much refrigerant as possible warm up the system s underhood components with engine and as al ready mentioned apply external heat to the accumulator if the system has one Tests performed for the SAE I MAC research program indi cate that you can remove a higher percentage of the refrig erant by applying heat and performing recovery after the early morning ambient chill has gone There are also differ
6. REVISED 12 2008 E f A E l E s Certification Training Manual Including Refrigerant Recycling and Service Procedures for Mobile Air Conditioning Technicians Best Service Practices Approved by the U S EPA for technician training requirements under Section 609 of the Clean Air Act This program is not intended to gauge the technical skills of technicians regarding the diagnosis and repair of motor vehicle air conditioners The basic goal of the technician training and certification program is to teach technicians how to properly recover and recycle refrigerant and why it must be done to protect the stratospheric ozone layer In addition the program provides information for servicing air conditioning systems with non ozone depleting alternate refrigerant SEE INSTRUCTIONS FOR TAKING TEST AND OTHER INFORMATION ON INSIDE FRONT COVER _ 1 NA am H E I I Important Notes Do not mix up tests or exchange tests with other individuals at your place of business All tests are coded with names matching assigned numbers Please review your test upon completion Any questions marked with more than one answer will be scored as incorrect Any question not marked will be scored as incorrect Completely fill in the block Bl to the left of the correct answer Do NOT mark with a check v or an x X General Information and Instructions You have r
7. tors abilities to pinpoint leaks 2 What should a technician look for when purchasing a new electronic leak detector Technicians should look at the type of sensor technolo gy used and whether they are comfortable with the pros and cons of that type They should also look at sensor life a typical heated diode sensor life is 150 hours detector sensitivity this should be compliant with SAE J1627 cur rently 0 5 oz year for HFC 134a and CFC 12 or J2791 for HFC 134a power requirements and battery life Practical considerations like the length and flexibility of the probe in order to get into hard to reach places what type of maintenance the unit requires and the unit s ease of use should also be considered 3 What is the best way to use an electronic leak detector High temperatures increase system pressure and therefore leak rates and actually help to find leaks Conversely cold temperatures especially below 60 F may reduce pres sure leak rate enough to make it difficult to find leaks According to the Interior Climate Control Standards Com mittee of the Society of Automotive Engineers the best procedures for using electronic leak detection are de tailed in SAE document J1628 a The document specifies that the user should perform leak detection in accordance with the equipment manufacturer s operating instructions and with the engine off b In order to get the best performance the system should be sufficiently
8. Current industry standards do not exist for determining refrigerant emissions from mobile air conditioning systems Test procedures are not common between production component suppliers in establishing leakage values This System Leakage Chart has been developed from industry experience of expected refrigerant leakage gains from system design resulting from technology changes It provides a rating value of various technologies that are currently available The Leakage Chart can be expanded as new technologies are offered and or developed This document provides the information to develop an Excel file template Leakage Chart for making system analysis It is not the intent of this practice to define the refrigerant emissions from a mobile air conditioning system It is to only define a system rating based upon the technology used Future development of SAE Standards for determining mobile air conditioning refrigerant emissions such as system static and dynamic min shed test procedures will provide a procedure for determining system emissions Publish in 2005 revised July 2007 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE System Components SAE J51 Automotive Air Conditioning Hose This document covers CFC 12 emission rates for refrigerant hose use on mobile air conditioning systems This document does not cover the hose coupling integrity SAE J2064 R134a Refrigerant Automotive Air Conditioning Hose The revised document ad
9. 4000 PPM by weight Air non condensable gases 330 PPM by weight EPA regulations require that certified CFC 12 recovery recy cling equipment must conform to the specifications listed in SAE standard J1990 The equipment must also have a label which states Design certified for compliance with SAE J1991 Purity of Recycled HFC 134a The SAE J2099 standard of purity for on site recycled HFC 134a states that the refrigerant shall not exceed the follow ing levels of contaminants Moisture 50 PPM by weight Oil 500 PPM by weight Air non condensable gases 150 PPM by weight EPA regulations require that certified HFC 134a recovery recycling equipment must conform to the specifications listed in the appropriate standard The equipment must have a label which states Design certified for compliance with SAE J2210 or J2788 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE 000273 RCA AUTOMOTIVE MH Design Certified by Underwriters Laboratories inc lor Compliance SAE J 2210 1991 ln u amp LISTED T VILA 5196 Recovery recycling machines used for mobile system service must bear a label showing that they meet the requirements of the appropriate SAE standard Certified by Underwriters Laboratories Inc to meet SAE J2788 superceding J2210 541578 Rev A Equipment manufactured after Jan 1 2008 will have a label similar to the above noting that the equipment meets SA
10. Refrigerant Leak Detection Capability TAT Pies Le Baie d 5 pam omar Chart A This chart demonstrates the effectiveness of various leak detection methods 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE 2 HIN Blefragerant Leak Detection Capcatilibr E78 e Bu si bt ele rim zm EIN ae Boni 3 Zo mile Rag eT gee cam Fam Deae Chart B This chart compares the effectiveness of SAE J 1627 and J2791 elec tronic leak detectors Using Electronic Leak Detectors Proper use of leak detection equipment is important since leaks may occur in locations not directly visible The fol lowing procedures are recommended by A C system man ufacturers to best identify system leaks and are also an overview of the SAE J1628 leak detection procedure The system should first be visually inspected by looking for traces of oil on refrigeration system components Oil traces can be indications of possible leak sites The vehicle s engine should not be running during the leak check since air movement from the engine cooling fan s can affect the detector s ability to locate leaks All fittings and components should be checked on all of their surfaces Leaks can be present at any point at the top or bottom of the part being checked Cleaning the surface with a clean cloth can be helpful Do NOT use any cleaning solvent To prevent contamination lea
11. of the MALS A Force po i ar the te important industry information to help and your butinest compete effectively MACS Worldwide Family of Publications T metly and the A C d member Ehraing a TP concerning i5 ri d f ar in Macs Tul include che ACTION SPT ati public ocu Semat eports providing all reprit Wath Uwe mot current ng E pii mg from itane and fedes on p the aille permete A servie m for Prey ACTION Magazine ACTION provides comprehensive technseal information and communication for the mobile air conditioning and cooling system industry The magazine is a prime tource of information n new technology service industry and govercnmert Published seven imes year MACS Service Reports This technical publication contains service bulletins tips and specific technical information not normaly found in service manuals Published monthly MAC CS Wo a No or 1 w id le l 5 ee Phone 215 631 7020 Fax 215 631 7017 Note To learn more about the EPA stratospheric protection program or to order publications call the EPA s Hotline at 1 800 296 1996 or check the EPA s website located at http www epa gov ozone title6 609 609 html Published by MOBILE AIR CONDITIONING SOCIETY MACS WORLDWID
12. refrigerant to be returned to a refrigerant reclamation facility that will process it to the appropriate ARI 700 Standard or allow for recycling of the recovered refrigerant to SAE J2788 specifications by 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE using SAE J2788 certified equipment It is not acceptable that the refrigerant removed from a mobile air conditioning A C system with this equipment be directly returned to a mobile A C system This standard supersedes the requirements of SAE J1732 Because of environmental concerns SAE J2788 recovery recycle standard established more stringent equipment performance features and requirements for on site recovery recycle and recharge of HFC 134a R134a in mobile air conditioning A C systems This standard is for HFC 134a R134a recovery extraction only equipment that is intended to be used in conjunction with the on site recovery recycling R R equipment used at service facilities for off site refrigerant reclamation or other environmentally legal use such as destruction of refrigerants or in another compound Published October 2007 Replacement Refrigerant Requirements Four documents were developed at the request of EPA to provide engineering guidelines for alternate refrigerants being considered for mobile A C systems SAE J1657 Selection Criteria for Retrofit Refrigerants to Replace CFC 12 R12 in Mobile Air Conditioning Systems This includes flammability ozone depleti
13. them removed refrigerant from vehicles at their facility If applicable they must also keep records documenting the sale of ozone depleting refrigerants A Word on Recovery only Equipment The operation of recovery only equipment is similar to the recovery feature of recovery recycling equipment How ever recovery only equipment is designed for the sole purpose of removing refrigerant from a system it does not recycle refrigerant for reuse Before it can be reused the refrigerant must be recycled through use of a recovery recycling machine which meets the appropriate SAE stan dard for either CFC 12 or HFC 134a or sent off site to be reprocessed to the appropriate Air Conditioning and Re frigeration Institute ARI ARI 700 specification If refriger ant is sent off site records indicating where the refrigerant was sent must be maintained for three years CFC 12 recovery only and recovery recycling equipment and its refrigerant tanks have SAE 3 8 inch service fittings HFC 134a recovery only and recovery recycling equip ment and tank fittings have 1 2 inch Acme threads Do not use adapter fittings with recovery only machines or their tanks Use of adapter fittings could result in contamination of refrigerant as well as A C systems Tanks designated for use with recovery only machines are gray in color with a yellow top and an identification label which reads DIRTY CFC 12 or HFC 134a DO NOT USE MUST BE REPROCESSED T
14. top off a system Facilities that typically only change or add fluids such as lube oil filter operations must have certified technicians and equipment All listed mobile A C system refrigerants removed during service cannot be vented to the atmosphere Alternate refrigerants currently listed by EPA cannot be vented and must be recovered and properly disposed of since EPA has not approved on site recycling equipment for these alternative refrigerants Recovery and disposal of any future alternate refrigerant s identified as accept able by the U S EPA will also likely be required Recovery only equipment for Significant New Alterna tives Program listed SNAP alternate refrigerants must meet EPA and or SAE equipment standards It is also permissible to only recover CFC 12 and 134a and other alternate replacement refrigerants In this circumstance the refrigerant must be sent off site for recycling reprocessing reclaim or disposal CFC 12 and HFC 134a removed from systems must be recycled before it can be re used even if it is to be reinstalled into the same system from which it was re moved Blends must be recovered and sent off site for proper disposal Under federal law it is legal to add refrigerant to a pre existing leaking system However some states and local municipalities may have laws prohibiting this practice It is the technician s responsibility to find out if a more stringent policy is applicable in th
15. 12 Systems Retrofitting of some of the CFC 12 fleet and continuing availability of CFC 12 has allowed continued servicing of vehicles that were originally designed to use it Until it is no longer available it is legal to store and use CFC 12 for servicing mobile A C systems However only technicians certified under section 608 or 609 of the Clean Air Act may purchase it For more information on EPA regulations applicable to mobile A C system service visit www epa gov ozone ti tle6 609 or call the EPA s Stratospheric Ozone Protection Hotline at 800 296 1996 Notes Montreal Protocol Working as Planned Scientists Say In August 2006 scientists said the ozone lay er of the Earth s atmosphere appears to have stopped thinning a clear sign that a 19 year old pact to phase out man made ozone destroying gases is working The research team led by Eun Su Yang of the Georgia Institute of Technology concluded that the ozone layer out side of the Earth s polar regions stopped thinning around 1997 ending a steady decline since 1979 These results confirm the Montreal Protocol and its amendments have succeeded in stopping the loss of ozone in the stratosphere said Yang whose study appeared in the September 9 2006 issue of the Journal of Geophysical Research At the current recovery rate the atmospheric model ing community s best estimates predict the global ozone layer could be restored to 1980 levels In
16. 6 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Application for Membership AHE HONDO om STATE IA LA EMAR ADOBE WER SITE ADDRES 200 Annual Dues Dissriburion 400 Annual Dues Manufacrurer Supplier 700 Annual Dues EdueationallTraining Facdiry 140 Annua Dues Mein Cannot thop owner officer of an entier dazributar or company General description of your business Hionthly and quarterly rates available Please contact the MACS office for details Distributor for following brands please list Percentage of business from AIC activities E Number of business locations operated Enrel me as MACS member Please send MACS Serrie Reports to via emal Is there anyone else you can recommend who might benefit from MACS membership ADDIT CITY STATE IP Enclosed is my check for 5 Please charge co please check Mastercard CARD E DATE Corse vr nue Fu DE Coie Bie pea peaks B E ri ete CLIE i i COPT THIS DCCUNENT BEFDBE FILLING OUT COMPLETE MAIL WITH HEHBERSHIP TO ADDRESS AT RIGHT MACS Worldwide offers these and other valuable services to its membership a 12
17. Information Report is to provide information on refrigerant issues of concern to the mobile air conditioning industry System Design Guidelines SAE J639 Safety Standards for Motor Vehicle Refrigerant Vapor Compression Systems This SAE Standard Practice is restricted to refrigerant vapor compression systems that provide cooling and or heating for the passenger compartment This document provides design standards for refrigerant containment and safety for these systems Also included are cautionary statements for the mobile air conditioning service industry to alert service technicians to the inadvisability and the possible health and safety effects associated with venting refrigerant during service It is not intended to restrict the use or further development of other types of refrigeration systems for passenger compartment cooling Should other systems be found practical this document may be amended or an additional standard safety practice created for such systems This document addresses only CFC 12 R12 HFC 134a R134a HFC 152a R152a a flammable gas and carbon dioxide R744 refrigerants To prevent system contamination and address safety issues all refrigerants used in mobile air conditioning vapor compression systems require unique service fittings The unique service fittings minimize the potential for system refrigerant contamination during service activity SAE J2727 R134a Mobile Air Conditioning System Leakage Chart
18. The service industry and EPA strongly recommend but do not require the use of this equipment You can also use an identifier to help confirm what type of refrigerant is in a container The identifier should conform to the specifications outlined in SAE J1771 this assures that the unit correctly identifies re frigerants Keep in mind however that even the best iden tier may not be capable of indicating all of the possible combinations of chemicals that may be in an A C system or storage tank The identifier cannot determine if the refrig erant meets the SAE J2776 purity requirements While not required by law the use of a refrigerant identifier is strongly rec ommended It can help you determine if a vehicle contains contaminated re frigerant that you would not want inside your recovery machine Identifiers can also provide an accurate indication concerning the amount of air that may be in an A C system or storage tank Ensure System Integrity As a first step in service always perform a visual inspec tion to spot obvious problems Since the service port caps serve as the primary seal for the service ports make sure that each service port in the system has a cap installed and that the caps seals are not damaged Missing or damaged service port caps are major leak sources After service on the system is completed make sure that each service port has a cap reinstalled and that all of the caps seal properly Check for Pressure i
19. a last resort you should be able to perform a refrigerant leak test g When all service has been completed leak test the system again to verify a complete repair 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE NS MS CERTIEICATION TRAINING MANIJA L4 VIN 2 Li i L oo V FN Jd K A N N J V F N JT L Li i iw d Y i 1 Y c Using Dye to Find Leaks Ultraviolet fluorescent trace dye systems are a popular choice for techs today in their efforts to hunt down elusive leaks Not only are they an inexpensive and easy to learn method of locating leaks they also have the advantage of giving the shop visual proof of a leak which can turn into an interactive experience with the customer A typical UV dye leak detection kit contains dye a dye injector or some other type of tool to introduce dye to a system an ultraviolet lamp and the correct goggles for the dye being used Always wear the goggles to protect your eyes from the UV light This kit also contains a special cleaner to remove traces of the dye after the leak is repaired Dye Formula Ultraviolet dye is a microscopic particulate suspended in a base fluid This base fluid varies from manufacturer to man ufacturer This particulate and base fluid when introduced into the refrigeration system mixes with the lubricant and is transported throughout the A C system When a leak o
20. charged with refrigerant to maintain at least 50 psi This may not be possible when the work area temperature falls below 59 F c When working with the detector care should be tak en to not contaminate the detector probe If cleaning ofa part is necessary do not use cleaners or solvents which may contain substances that the detector will sense d A visual inspection should be made for signs of lu bricant leakage damage and corrosion and each damaged area should be inspected with the de tector Other areas to concentrate on are fittings couplings controls valves service port caps brazed or welded areas and component attachment points Take care to inspect the entire system so no potential source of leaks will be missed e Toobtain the best chance of detecting the leak move the probe no more than 1 2 inches per second at no more than 1 4 inch from the surface If you find a po tential leak verify it by blowing shop air around the area and retesting f Leak testing of the evaporator core is a challenging task This is best accomplished by running the air conditioner blower on high for at least 15 seconds and then turning the blower off Wait for refrigerant to accumulate in the evaporator case the manu facturer of the equipment will specify the time By inserting the leak detector probe into the blower re sistor hole if near evaporator condensate drain or other appropriate opening use the heater or vent duct as
21. detector s in struction manual for more information To help confirm a suspected leak place aluminum foil or plastic wrap and tape it around the connection or component If there truly is a leak after a few minutes refrigerant should accumulate inside the plastic wrap or foil Make a small hole in the foil or wrap at the lowest point possible and place your leak detector probe at the hole The detector will indicate refrigerant found if a leak is actually present 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Why is the type of dye important A dye must be compat ible with the system s lubricant the mineral oil that is used in CFC 12 systems and the PAG oil that is used in HFC 134a systems While some companies market universal dye no vehicle manufacturer has approved a non PAG compatible dye for HFC 134a systems So check that the dye to be used in an HFC 134a system has at least been certified to meet the SAE J2297 requirements How Much Dye Is Too Much It is important that dyes be safely and properly used Exces sive dye can result in compressor damage Check with the manufacturer s recommendation realizing that the amount depends on the dye type particularly with lubricant specific dyes The basic rule of thumb is 1 4 oz per system Lamps amp Goggles Most manufacturers design their UV lamps to work best with their own dyes so the dye particles fluoresce with their lamp for the best wavelength and u
22. determine if the system will provide cooling If you intend to operate the compressor the system must contain its specified amount of refrigerant CAUTION To prevent possible compressor damage do not operate the compressor without the full charge of refriger ant as specified by the vehicle manufacturer Once the system contains sufficient refrigerant adding more will not increase pressure As shown in the curve on the following chart when the system has about 1596 of its total refrigerant charge a saturated condition occurs and the pressure will not increase if more refrigerant is charged into the system Partial Refrigerant Charge Saturated System Pressure with liquid vapor at 85 degrees F Refrigerant amp Air EZ Pure Refrigerant o S N z o 2 2 I o 5 a D g a o c 2 2 o o 6 7 8 9 10 11 12 13 14 15 16 Percent of System Refrigerant Charge No Vacuum Prior Vacuum Chart C The curves found in Chart C also compare a system with a reduced amount of refrigerant with and without air Without compressor operation the same pressure will be present in all parts of the system Since you will not vent refrigerant added for leak testing the air would be removed when the refrigerant is recovered and recycled System pressure also has a direct correlation to the temper ature in the work area With the area having a temperature of 50 F the pressure will be in the rang
23. does not comply with SAE or Section 609 of the Clean Air Act requirements SAE J1990 Recovery and Recycle Equipment for Mobile Automotive Air Conditioning Systems This covers equipment certification for recovery recycling CFC 12 to meet the standard of purity Revised February 1999 SAE J1991 Standard of Purity for use in Mobile Air Conditioning Systems This identifies the purity level of recycled R12 refrigerant after a contaminated sample has been processed in SAE J1990 Revised February 1999 SAE J2099 Standard of Purity for Recycled HFC 134a R134a for use in Mobile Air Conditioning Systems This identifies the purity level of recycled R134a refrigerant after a contaminated sample has been processed in SAE J2788 Revised February 1999 SAE J2209 CFC 12 R12 Refrigerant Recovery Equipment for Mobile Automotive Air Conditioning Systems This covers equipment certification for recovery of CFC 12 from mobile A C systems to be processed in SAE J1990 recovery recycling equipment or be sent off site for process to meet ARI 700 purity level Revised February 1999 SAE J2296 Retest of Refrigerant Cylinder Refrigerant containers used with recovery and recovery recycle equipment must be inspected every 5 years to assure their safety This document covers the retesting of these containers Revised November 1999 SAE J2788 HFC 134a R134a Recovery Recycling Equipment and Recovery Recycling Recharging
24. fact scientists with the World Meteorological Organization and the United Nations Environment Programme concur that the ozone layer over the planet s inhabited northern and southern mid latitude areas should reach a pre 1980 recovery level by 2049 Excerpt from Greenwire 31 August 2006 E amp E Publishing LLC 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE NM 5 SERVICE PROCEDURES FOR MOBILE AIR CONDITIONING SYSTEMS Caution When using recovery recycling recharge equip structions Failure to follow these instructions could result ment while it is very important to follow the general in personal injury damage to the equipment or A C sys service procedures outlined in this manual it is also very tems or improper or inadequate refrigerant recovery recy important to follow your equipment s manufacturer s in cling and containment Safety Precautions amp Warnings 1 ALWAYS wear eye protection when servicing air conditioning systems or handling refrigerant 2 Avoid breathing refrigerant and lubricant vapor or mist Exposure may irritate eyes nose and throat If accidental discharge occurs ventilate the work area 3 Do not allow refrigerants to come in contact with open flames and high temperature surfaces Decomposition is hazardous and can occur if refrigerant is exposed to high temperatures open flames hot metal surfaces etc 4 134 is not flammable at normal ambient temperatures and atmospheric
25. in skin cancer and cata racts It may also cause damage to the human immune sys tem The reduction of stratospheric ozone may also reduce crop yields and alter aquatic ecosystems Growing awareness about the threat to the global envi ronment and the type and amount of refrigerant used in mobile air conditioning systems has resulted in system de sign changes new service procedures and equipment to reduce system lifetime emissions The ozone layer is located in the stratosphere about 10 to 30 miles 16 to 48 kilometers above the earth s surface CERTIFICATION TRAINING MANUAL MORE ON OZONE DEPLETION CFCs and their Affect on Ozone Possible depletion of the ozone layer resulting from CFCs was first raised in 1974 Research indicated that chlorine released from CFCs could migrate to the stratosphere and destroy ozone molecules Molina and Rowland 1974 Some CFCs have an atmospheric lifetime of more than 120 years which means they do not break down in the lower atmosphere As a result they migrate slowly to the strato sphere where higher energy radiation from sunlight strikes them releasing chlorine The link between CFCs and ozone depletion is supported by scientific evidence CFCs have been widely used and when released migrate to the upper atmosphere Because CFCs are very stable and heavier than air they do not LTRAVIOLET Chlorofluorocarbon pus molecule Chlorine atom N xt T 4 poem I 1 4
26. material compatibility of trace dye material with mobile A C systems Published September 1996 SAE J2298 Use of Refrigerant Leak Detection Dyes for Service of Mobile Air Conditioning Systems This covers the procedures including safety requirements when using trace dye to determine if the A C system has a refrigerant leak Published September 1996 SAE J2299 Performance Requirements for Leak Detection Dye Injection Equipment This document establishes the requirements for the equipment required to install trace dye material into the refrigerant circuit of a mobile A C system Published September 1996 SAE J2670 Stability and Compatibility Criteria for Additives and Flushing Materials Intended for Use in Vehicle Air Conditioning Systems Using R134a The purpose of this standard is to provide testing and acceptance criteria to evaluate the stability and compatibility of chemicals including flushing materials and additives e g to enhance lubrication durability cooling performance energy performance prevent fix leaks intended for use in R134a vehicle air conditioning systems Successful completion of all requirements contained in this specification indicates acceptable compatibility with the A C system materials but does not suggest that the additive improves system performance in any way This SAE standard applies to any and all additives and chemical solutions intended for aftermarket use in the refrigerant circui
27. of Mobile Air Conditioning Systems This document provides guidelines for the technician when using an electronic leak detector in determining a system refrigerant leak Published November 1998 SAE J1989 Recommended Service Procedure for the Containment of CFC 12 R12 This document covers the technician refrigerant recovery recycling procedures when servicing CFC 12 R12 mobile A C systems and identification of excess NCG s Revised November 1998 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE MS SAE J2211 Recommended Service Procedure for the Containment of HFC 134a R134a This document covers the technician refrigerant recovery recycling procedures when servicing HFC 134a mobile A C systems and identification of excess NCGs Revised November 1998 Service Equipment SAE J1627 Rating Criteria for Electronic Leak Detectors This document establishes the criteria for electronic leak detectors to identify refrigerant leaks Published August 1995 SAE J2791 HFC 134a Refrigerant Electronic Leak Detectors Minimum Performance Criteria The purpose ofthis SAE Standard isto establish minimum performance criteria for electronic probe type leak detectors intended for use in automotive air conditioning systems with HFC 134a refrigerant Improved design requirements for refrigerant containment of HFC 134a mobile air conditioning systems have resulted in reduced annual system refrigerant emissions Identification of potenti
28. on site recycled refrigerant Based on that early study SAE and industry have identified that only uncontaminated CFC 12 and HFC 134a refrigerant removed from a mobile A C system and recycled on site us ing equipment meeting SAE Standards is acceptable for re use All other used or contaminated refrigerant from other sources must be sent off site for processing and must meet the specific ARI recycled purity specification Summary of Standards At the request of the U S Environmental Protection Agen Cy SAE Interior Climate Control Standards Committee es tablished working groups to address the needs of the auto industry regarding environmental concerns This summary includes SAE documents that have been developed for sys tem design requirements refrigerant emissions contami nation and handling of refrigerants used in the mobile air conditioning industry With the requirements to phase out HFC 134a mobile air conditioning systems in Europe starting in 2011 replace ment refrigerants will be entering the global marketplace The SAE Interior Climate Control Standards Committee is developing new international standards and practices ad dressing the use of new alternate refrigerants for system design service equipment and technician procedures Industry Criteria and Guidelines SAE J2219 Mobile Air Conditioning Industry and Guidelines This document was originally published in 1991 and revised in 1994 The purpose of this SAE
29. over the South Pole ers found that an accelerated deterioration of the ozone layer had been created by a combination of four elements atmospheric ice crystals upper atmospheric vortex winds the change from total darkness to sunlight AND damaging CFCs The four factors when combined together made the ozone deterioration process even faster When scientists began studying ozone depletion in the early 1970s they also investigated several natural phenom ena such as volcanoes and evaporation of seawater Vol canoes produce hydrochloric acid However most volcanic discharges are not powerful enough to reach the strato sphere Chlorine evaporation from seawater is dissolved in rain and does not reach the stratosphere Chlorine pro duced by volcanoes or oceans does not leave the tropo sphere and poses no threat to the ozone layer However CFCs being extremely stable do not release chlorine until they reach the stratosphere In December 1994 NASA announced that satellite data gathered over a three year period confirmed that CFCs are the primary source of stratospheric chlorine Because of the long atmospheric lifetimes of CFCs it will take many decades for the ozone layer to return to its for mer concentration As CFC levels are reduced the natural atmospheric process will rebuild the ozone level Until that time increased UV levels can lead to a greater chance of overexposure to UV radiation and the health and environ ment
30. platforms These tests were performed at 100 F and cover refrigerant charges ranging from 16 to 30 ounces The factory specified re frigerant charge is 22 4 ounces for the integral condenser receiver drier IRD system 28 ounces for the expansion valve TXV system and 26 ounces for the orifice tube OT accumulator system In Table 1 notice how little the pressure changes in some systems as the refrigerant charge diminishes below the fac tory charge amount For example on the TXV system a 20 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Table 1 System Charge System Charge 02 16 17 6 18 19 20 224 2 High Side PSIG 23 3 3 39 2 5 5 3 0 2 20 8 22 4 26 28 30 igh Si 201 2 230 2 235 2 238 2 39 Panel Outlet Temperature vs Hefrigerant Charge iu LPS bee Fi LE fa il m m aj a 0 AD Pares Temp Chart D percent reduction in refrigerant charge from 28 oz to 22 4 Oz resulted in the high side pressure dropping only 4 psig from 300 to 295 On the IRD system a loss of 20 percent of the charge resulted in the low side pressure dropping only two tenths of a pound from 31 8 psig to 32 psig It is obvi ous that pressure changes resulting from reduced charge can be very small and may not be reliably indicated by pres sure gauge readings Further the data in these charts was obtained using laboratory instrumentation Attempting to identify these small pressure changes
31. pressure However tests have shown it to be combustible at certain pressures and ambient temperatures when mixed with air under pressure in a sealed environment Service equipment or vehicle A C systems should not be pressure tested or leak tested with com pressed air 5 PAGlubricant is hygroscopic absorbs moisture Containers must be kept tightly closed 6 PAG lubricant can be a skin irritant Protective impervious gloves are required to prevent lubricant contact with the skin To help avoid skin contact mineral oil should be used to coat o rings and seals prior to installation Also since PAG lubricants absorb moisture using mineral oil reduces the potential for fitting corrosion 7 PAG lubricants can cause damage to paint plastic parts engine drive belts and coolant hoses Care should be taken to prevent PAG lubricants from coming into contact with these items 8 Failure to follow instructions provided by A C system service equipment manufacturers could result in personal in jury or equipment damage 9 To prevent refrigerant cross contamination use separate service equipment for each refrigerant Lubricant and re frigerant left in hoses and equipment can be a source of cross contamination 10 NEVER transfer refrigerants to a cylinder or tank unless it is Department of Transportation approved for refilling DOT approval is indicated by the designation DOT 4BA or DOT 4BW stamped on a tank s collar handle 11 Ifa refriger
32. pump isn t performing properly not per forming a deep vacuum or in the interest of saving time you shortcut performing a deep vacuum you could end up leaving refrigerant in the system If you then recharge the system to specification you will end up with an overcharge This costs you money because you re using more refrigerant than necessary and the more jobs you do this way the more money you re losing However and possibly even worse overcharging a system during service can set the stage for future operational problems Use of SAE J2788 equipment will assure improved refriger ant recovery during service Improperly Recycled Refrigerant It is important to make sure that recycled refrigerant does not contain air non condensable gas in excess of allow able amounts If recycled refrigerant contains too much air high system operating pressure will occur and pressure operated refrigerant controls will have a different control set point This will result in loss of air conditioning perfor mance and possible system damage Properly operating recovery recycling equipment will re move excess air Many newer R R machines have an auto matic air purge feature which if working properly should assure that its recycled refrigerant will not contain exces sive levels of air However many older R R machines re quire a manual air purge operation Make sure you understand which type of air purge feature your machine has and f
33. retrofitting a CFC 12 R12 system to HFC 134a R134a while preserving performance and integrity of the air conditioning A C system The steps outlined in this procedure are complete when combined with good service practices and the vehicle manufacturer s recommendations if available for retrofitting their models Separate service equipment for CFC 12 R12 and HFC 134a R134a including refrigerant recovery recycle R R service manifolds vacuum pumps and charging equipment shall be used to preserve the purity of the refrigerants and the mobile A C systems This procedure will minimize release of refrigerant to the atmosphere and will preserve the integrity of the recycled CFC 12 R12 and HFC 134a R134a supplies This document applies to A C systems used to cool the passenger compartment of automobiles light trucks and other vehicles with similar CFC 12 R12 systems Due to technical advancements in recent years this procedure is recommended for common vehicle platforms produced in the mid 1980s and later Vehicles produced before this time period may require additional retrofit requirements A C systems used on mobile vehicles for refrigerated cargo that have hermetically sealed systems are not covered by this document This document is only complete when combined with the requirements of SAE J1657 Selection Criteria for Retrofit Refrigerants to Replace CFC 12 R12 in Mobile Air conditioning Systems SAE J1662 Compatibility of
34. shops chain or fran chised repair shops new and used car and truck dealers rental establishments radiator repair shops mobile repair operations vocational technical schools because instruc tors are paid farm equipment dealerships and fleets of vehicles at airports Technician Training and Certification Requirements Technicians using approved equipment must be trained and certified by an EPA approved organization To be cer tified technicians must pass a test demonstrating their knowledge in the use of refrigerant recovery recycling equipment the regulatory requirements the impor tance of refrigerant containment and the effects of ozone depletion and environmental change Overlap Between Sections 608 and 609 of the Clean Air Act Section 608 of the Clean Air Act directs the EPA to establish requirements to prevent the release of ozone depleting 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE and certain other refrigerants during the servicing repair or disposal of appliances and industrial process refrigeration systems This includes the scrapping salvage of vehicles that have a mobile A C system Section 608 covers pro cedures involving motor vehicle air conditioners MVACs that are not covered by Section 609 such as the disposal of MVACs Below is information concerning specific areas where the overlap between these two sets of regulations may require clarification Section 609 of the Clean Air Act esta
35. speci fication 26 ounce orifice tube system The undetectable problem is the compressor outlet temperature change and this is not identifiable by just looking at the system 30 Low Side Pressure Compressor pressures When the refrigerant charge is reduced by twen ty percent to 20 8 oz compressor outlet temperature in creased from 150 F to 182 F Increased system operating temperatures reduce durability This industry data proves several points To provide your customer true professional service don t attempt to estab lish system refrigerant charge using pressure readings or by using top off procedures If you have any question about the amount of refrigerant in a system remove the charge evacuate the system and install the correct amount It s the only way to do it right 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE CERTIFICATION TRAINING MANUAL INCORRECT SYSTEM CHARGES SOME REASONS WHY Following are several more reasons that A C systems end up getting charged with the incorrect amount of refrigerant Making an Unintentional Mistake While Determining the Charge Amount One reason for incorrect charge is making an uninten tional mistake while determining the recharge amount We sometimes see this because a vehicle manufacturer may find out long after a vehicle hits the street that they can get better A C performance by incr
36. sure to maintain your crimper and always use the proper dies for the particular job Beyond that however we have to admit that the by the book procedure is one that is not always easy to follow It includes making sure that the fittings and hoses are a within tolerance fit and that the crimp meets the dimensions specified Do you just cut off the needed length of bulk hose insert ing the needed fittings and turning the crimper s forcing screw until the joint seemed tight enough If so what you re doing might not be producing a coupling that will not leak A major issue is the hose which has greater size tolerances than the metal fittings There are cases where the wrong size fitting was inserted so loose that if you inverted the hose the fitting might drop off We also know of shops that believe one crimper fits all and use a hydraulic crimper on an A C hose It may produce a tight crimp but it s been known to crack the hose s barrier lining The conscientious shop can do a great job when it comes to the field assembly and repair of A C system hoses Measure Twice Crimp Once Is your bulk A C hose a quality brand and do you have a hose cutter that produces a neat end Start by measuring the hose itself Crimper and fitting manufacturers may provide specs for wall thickness for different size hoses and there are some hose brands with tolerances that could go outside the listed range Make sure you know what you have
37. that have sealing surfac es may fail and result in leaks More information regarding hose assemblies and hose couplings can be found on the following pages Page 37 All hoses used with mobile A C system service equipment must be equipped with shut off valves The shut off valves may be either manual or automatic SAE standards stipulate that the shut off valves must be located within 12 inches 30 cm of the vehicle end of the service hose but some equipment manufacturers incorporate the shut off valve in their quick couplers Page 37 Air can be introduced into the refrigerant supply when refrigerant is recovered if there are any leaks in the A C system or the service hoses Pages 41 and 42 Information regarding repair of hose and proper hose coupling is addressed on these pages Page 48 When the mobile industry changed refrigerants from CFC 12 to HFC 134a new unique quick couple service fittings were developed to reduce venting and possible mixing of refrigerants during service of mobile A C sys tems New unique quick couple service fittings have been developed for R744 carbon dioxide and HFC 152a mobile A C systems and are identified in J639 O rings and Seals O rings and seals have a major role in refrigerant contain ment More detail regarding these important A C system components can be found on the following pages Page 5 Changes in systems designs were required to assure that HFC 134a systems performed equal t
38. the right is representative of the type of condensers used in many HFC 134a systems 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE t us CERTIFICATION TRAININ using many different formulations of Polyalkylene Glycol PAG lubricants with various additives SAE standard J639 requires vehicle and A C system manufacturers to identify their recommended lubricant on the system s information label It is recommended that different types of PAG lubri cants not be mixed A vehicle s A C system information label lists the type of lubricating oil that the system requires FEDERAL REGULATIONS AFFECTING MOBILE A C SYSTEM SERVICE FC N AN N N 4 IT 1 V d V N J 5 BE D HIGH E SERVICE we tune TOURE mt METHODS kay SEE SERVICE Ma erence TEE MANUAL FOR SYSTEM COMPLIES WITH SAE Sane ALLIE TT ao REFS BAT TOL ee gt Bede ve H Linda Moto Co Lia A Mu Section 609 of the Clean Air Act gives the EPA authority to establish standards and requirements regarding servicing of mobile A C systems On July 14 1992 the EPA published the final rules regula tions implementing this section of the Act 40 CFR Part 82 Under the U S Clean Air Act it is illegal to vent chemicals used in mobile air conditioning systems into the atmo sphere Therefore on site recovery
39. using a service mani fold gauge set to charge the system is not realistic It s also plain that pressure changes are not linear to the amount of refrigerant in the system A system may be 10 or 20 percent under the desired refrigerant charge amount and still show apparently near normal pressure gauge readings Measuring high and low side pressures will not provide any indication concerning the amount of refriger ant in a system L I b 1 i LI ij j jil a a a i TXV Panel Temp OT Por Tang Use Chart D to see the effect of reduced refrigerant charge on panel outlet temperatures Again the changes are small and sometimes surprising At 20 percent below the speci fied charge except for the OT system the same approxi mate outlet temperature was achieved Measuring outlet temperature will not provide any indication of the amount of refrigerant in a system Lubricant circulation in the system relies upon a proper refrigerant charge and inadequate refrigerant and there fore lubricant flow in the refrigerant circuit will result in in creased compressor operating temperature These higher operating temperatures can result in damage to the com pressor lubricant and flexible hoses and seals Table 1 above and Chart E on the next page compare the effect of reduced refrigerant charge on system pres sure in three types of single evaporator syste
40. 0 24 ounces Nissan is not totally consistent at least not between the Nissan Maxima and the Infiniti M45 models No tolerance is specified for Infiniti just a single number CERTIFICATION TRAINING MANUAL Nissan Maxima label shows refrigerant capacity in pounds and kilograms to two decimal places and a tolerance to three decimal places AIR CONDI TIONER AI o T OR ex i ANT DU COMPRESSEUR D ed AC COMPRESSOR BAIL ANTE COMPRESOR VAR ANT NSSAN UV Luminous KLHOO PAGSO Infiniti MX45 label shows refrigerant capacity in pounds and kilograms but With no tolerance listed The bottom line is that it s a good rule of thumb to have a combination of equipment and to work out a method that will always enable you to be able to charge within 596 of the specs If you have to convert between metric and Eng lish don t try to do itin your head or even with pen and pa per Small calculators are cheap you probably have a few in your shop now and you can tape a conversion chart to the underside for easy reference Conversion Chart Ounces oz to pounds Ibs divide by 16 Pounds to ounces multiply by 16 Ounces to grams g multiply by 28 4 Grams to ounces divide by 28 4 Pounds to kilograms kg divide by 2 205 Kilograms to pounds multiply by 2 205 Kilograms to ounces multiply by 35 27 Ounces to kilograms multiply by 0 0284 Don t guess at U S to metri
41. 26 4 to 28 16 ounces although it s appar ent VW is using 25 grams per ounce and 50 grams as equal to two ounces for the plus tolerance So adding two full ounces to the base converted specification of 26 4 ounces would be logical in this case although at 28 4 it wouldn t round up to 29 ounces It means you have to charge the sys tem with 27 28 ounces Note DO NOT assume that 25 grams is an acceptable conversion value to ounces for the ENTIRE charge only for the tolerance If your machine is calibrated in pounds use the low and high numbers divided by 16 to get the range 26 4 to 28 4 ounces equals 1 65 to 1 78 lbs round up to 1 7 to 1 8 lbs If the machine is calibrated in kilograms just divide the numbers at each end of the range 700 800 grams by 1000 to get kilograms and that would be 0 7 to 0 8 kg This Volkswagen label gives refrigerant capacity in grams along with the plus tolerance notice there s no minus so the range is 750 800 In this case although ounces are not listed the specification tolerance of 50 grams can be rounded off to two ounces in any conversion Nissan uses pounds and kilograms and if your machine is calibrated in pounds please notice that the plus minus tol erance is just 0 055 Ib which is 0 88 ounces less than the 0 1 Ib on most decimal scales Here again take the range and aim for something within it The specified charge is 1 21 Ibs so the range is 1 155 to 1 265 Ibs or 18 48 to 2
42. Complete Refrigerant RecoVOLV CE vH ed RATE EX TIC een ERU PIC UC CR 16 Improperly Recycled Refrigerant 5 mace ree RR CERE coton 18 VS e AES e e a e EAT COT OTT 18 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Best Service Practices for Mobile A C System lt 21 Sources of Refrigerant EMISSIONS dest er E ER etit d EET TEE el di ait PLE CM LESEN 21 Checking Mobile A C Systems for Bu RE 21 Using Electronic Leak Detectors es cessus uaa d RER RI ERA IER eee ae dE oi 22 Another Big Reason to Find and Fix Refrigerant Leaks 23 SIN ee de ce ton 24 DS PO DERI da 24 How Much Dye TOO MC 25 Lampes OUO a a da da on US TE 0 25 Before You Begin Using UV Dye to Find Leaks 25 Choosing Your Delivery System ssssseeeeeeeeeeeeeee enhn hens 25 LOOKING TOL LOOKS a cages EREE nn a D en a oo EP 25 PUSTNO G SV SUING cone TURPE TURA ed EIU SEP PIDEN S 26 ATOS ON EMA CAO eser RO ce cir cece cee Ces FEN FERE EDI aoe eset eee ee eee 27 Desiccapicrallute sedeo EEI 28 Properly Charging and Recharging Mobile
43. DE SAE J2196 Service for Automotive Air Conditioning SAE J2209 CFC 12 Recovery only Equipment HFC 134a SAE Documents SAE J1732 HFC 134a Recovery only Equipment superseded by SAE J2810 SAE J2099 Standard of Purity SAE J2196 Service Hoses for Automotive Air Conditioning SAE J2197 HFC 134a R134a Service Hose Fittings for Automotive Air Conditioning Service Equipment SAE J2210 Specifications for Recovery Recycling Equipment superseded by SAE J2788 SAE J2211 Service Procedures SAE J2776 Refrigerant Purity and Container Requirements for New HFC 134a 1 1 1 2 Tetrafluoroethane Refrigerant Used in Mobile Air Conditioning Systems SAE J2788 Specifications for Recovery Recycling Recharge Equipment SAE J2810 HFC 134a Recovery only Equipment Dual Refrigerant Recovery Recycling Equipment 12 134 SAE J1770 CFC 12 HFC 134a Recovery Recycling Equipment More Complete Refrigerant Recovery Ongoing studies aimed at reducing refrigerant emissions determined that existing equipment did not remove the entire refrigerant charge during recovery Because of this new SAE standards for recovery and recharge equipment were established In 2007 recovery recycling equipment standard J2210 was superseded by SAE J2788 The new J2788 equipment pro vides more complete refrigerant recovery and also estab lishes refrigerant charging requirements providing greater accuracy New recovery recycl
44. E No part of this publication may be produced in any form in an electronic retrieval system or otherwise without the prior written permission of the publisher National Office Box 88 Lansdale 19446 Phone 215 631 7020 Fax 215 631 7017 E mail info macsw org Website http www macsw org President Elvis L Hoffpauir MACS Technical Advisor Ward Atkinson Certification Training Manual Including Refrigerant Recycling and Service Procedures for Mobile Air Conditioning Technicians and Best Service Practices 2008 Mobile Air Conditioning Society Worldwide All rights reserved
45. E AIR CONDITIONING SOCIETY WORLDWIDE 5 5 cs CERTIFICATION TRAINING MANUAL Option 2 If the leaking system is not repaired it must be returned to the customer with at least the same amount of refrigerant that it contained upon initial inspection Note Some state and local laws have additional require ments regarding this aspect of A C service If the A C system had no pressure at first inspection any refrigerant added to the system is owned by the service facility If the facility has a policy not to charge leaking sys tems this is explained to the customer up front and the customer declines to have the leaking system repaired all added refrigerant can be removed Refrigerant added to a system for performance or leak testing cannot be vented to the atmosphere It must be recovered The Effect of System Design on the Refrigerant Recovery Process When refrigerant is removed from the system the lowering of pressure results in some of the system components be coming cooler This component cooling effect makes com plete refrigerant removal in a short period of time more difficult To remove as much of the refrigerant as possible during the recovery process systems equipped with orifice tubes and accumulators require more time than systems equipped with expansion valves receiver driers This is mainly be cause of the design differences between accumulators and receiver driers being larger than receiver drier
46. E Standard J2788 super seding J2210 Service Equipment Hoses All hoses used with mobile A C system service equipment must be equipped with shut off valves The shut off valves may be either manual or automatic SAE standards stipulate that the shut off valves must be located within 12 inches 30 cm of the vehicle end of the service hose but some equipment manufacturers incorporate the shut off valve in their quick couplers These automatically shut off the flow of refrigerant when the hoses are disconnected Fittings that are unique to individual refrigerants must be permanently attached to the vehicle end of service hos es Adapters for different refrigerants different systems or different service port designs may not be attached to ser vice hoses then removed and replaced with adapters for a different refrigerant Equipment Certification To comply with Section 609 of the Clean Air Act recovery recycling equipment must be certified to SAE specifica tions Recovery recycling equipment used for commercial refrigeration and not certified to SAE standards does not meet the federal compliance requirements and cannot be used To prevent refrigerant contamination recovery recy cling equipment must only be used with one designated refrigerant Equipment Registration It is the responsibility of the recovery recycling equipment owner or another responsible officer to notify the EPA that they own approved equipment The i
47. FICATION TRAINING MANUAL into the stratosphere travel globally and adversely affect the health and welfare of other countries The United States for example has been one of the largest producers and consumers of the world s CFCs Other na tions also have been significant users Therefore to protect the ozone layer an international solu tion was critical Montreal Protocol Recognizing the global nature of the problem on Septem ber 16 1987 in Montreal Canada 24 nations and the Eu ropean Economic Community EEC signed the Montreal Protocol on Substances which Deplete the Ozone Layer The U S and other countries signed the Protocol agreeing to phase out production of ozone depleting substances The 1990 Clean Air Act Amendments incorporated the Protocol s original phase out date the year 2000 In 1992 then President Bush pledged to halt almost all U S pro duction of CFCs by the end of 1995 The Chemicals Listed below are chemicals controlled by the Montreal Pro tocol and their associated ODP Ozone Depletion Poten tial values as well as their GWP Global Warming Potential values An ODP value is a measure of a chemical s relative ability to destroy ozone molecules in the stratosphere A GWP is a measure of a chemical s relative ability to produce a global warming effect The higher the ODP value the greater a chemical s poten tial to destroy ozone in the stratosphere The higher the GWP value the greater a ch
48. ICATION TRAINING MANUAL 09 To assure proper performance vacuum pumps must be serviced at the inter vals specified by their manufacturers Vacuum pump service usually consists of not much more than changing the vacuum 5 oil Typical vacuum pump oil change intervals run from the oil needing to be changed after ev ery 10 hours of pump operation up to perhaps after every 25 hours of pump operation Consult your vacuum 5 operational manual to find out how often you need to change its oil sing and removal of air Incomplete refrigerant removal in troduces the potential of overcharging a system which can result in system performance problems Experimentation has shown that even when the low side gauge reads 28 or 29 inches of vacuum the inside of the system has not actually reached that level of vacuum The gauge reading more indicates vacuum in the service hose not in the system Consider that the small openings in the service valve cores are major restrictions It is very difficult to reduce the ac tual system to 28 or 29 inches of vacuum and even with a very good vacuum pump it can take a long time There fore manufacturers suggest evacuation times of 30 to 45 minutes to assure that an adequate evacuation has been performed When it comes to removing moisture the entire system not just the service gauge reading must be below 29 inch es of vacuum Actual moisture removal does not start un til the system has
49. ION OF THE PROBLEM Copyright 2006 2008 The Mobile Air Conditioning Society Worldwide All Rights Reserved 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE CERTIFICATION TRAINING MANUAL AIC HEATING VENTILATION COOLING SYSTEM CHECKLIST VEHICLE Year Make Model i ______ Engine u System Type O R134a O R12 0 Retrofitted O Front 1 Rear CUSTOMER J Phone Date Address State Zip Refrigerant I D Analysis R134a R12 _ Air amp Other Gauge Readings High Side psi Low Side psi RPM COMPONENT _ OK REPAIR COMPONENT OK REPAIR Ru NENNEN 14 Electric Cooling Fan s E Tension i Belt Tensioner pF PUR sfidler Pulle Surge Suppression Diode 7 O 1 Electrical Connections Jg 19 Thermostat 6 Condenser m 7 Receiver Drier A Drier Accumulator Mounting Fittings Con nections AIC Hoses and Lines Leaks Fittir gs Connections T 40 Expansion Valve MEME Leaks _ __ Sensing Bulb 9 oO 28 Blower Motor Op eration Insulation m 7 27 AICIBlowerlFan Relays a m 41 Orifice Tube 28 Underhood Switches Controls Sensors Fittings Broken a a Leaks a Electrical Connections A 12 Fan ShroudiSasie a a Operation _ m EFI 5 a Leakag 5
50. Measuring hose wall thickness may seem unnecessary but if you look closely at the hose and the fitting you ll see why it s important Unless the hose wall thickness is within specs the fitting s ferrule might not crimp the fitting s neck properly If it meets the specs you can use the hose Be sure to mea sure the outside diameter at both ends of the needed length of bulk hose before you cut Some tolerances may be allowed in the hose wall thickness ranging from plus minus 0 018 0 028 inch depending on the type of hose and its diameter Good hose should be within tolerance not close to the limits Don t try to make do with out of tol erance hose or by over crimping the wrong size fitting 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE A NM 5 Note that the use of hose wall thickness vs outside diam eter is part of one manufacturer s system Another manu facturer might choose outside and inside diameters for the specifications that help produce field assembled hoses that meet J2064 Lube the hose end with refrigeration oil and insert the fit ting Although it won t be a difficult force fit it shouldn t be drop off loose either even with the lubrication The hose end should be visible in the small inspection hole on the side or end of the ferrule If it isn t visible it isn t fully in serted and you could get a poor crimp Appearance Counts Inspect the crimp for a good visual appearance It should be uniform and
51. OESENT A a 46 Improved HFC 134a 5VSEBIHTIS oa tena lad EN 4S dor bab abren 47 Appendix SAE Standards Applicable to Mobile A C System Service 48 Equipment Certification Form hh hh hehehe 53 EPA Regional Lois sebo serta Edad Vane abad ch a da Pda eie o PATER REN 54 Air Conditioning amp Heating Customer Questionnaire 55 Heating Ventilation Cooling System Checklist 56 See page 51 for information on how to purchase Standards from SAE International Guidelines for Repairing Mobile Systems To minimize refrigerant emissions and have properly operating systems it is important that they be properly serviced The following are some of the recommended in dustry procedures as identified in this manual Note The following page numbers and excerpts are provided to as sist the reader find relevant information regarding repair and replacement of components in the manual The reader is referred to pertinent sections of the manual where the excerpts may be reviewed in their full context along with additional relevant information The following provides an overview and the reference page covering more detail Compressor While the fix for a leaking or failed compressor is usually
52. Retrofit Refrigerants with Air Conditioning Materials Seals hoses and rings used in CFC 12 systems may not be compatible with some alternate refrigerants and could break down causing system failures This document covers test procedures for establishing material compatibility Published November 1998 To obtain further information or to purchase documents from SAE International visit their website at www sae org climatecontrolstds Or contact USA Toll Free 1 877 606 7323 Outside US and Canada 1 724 776 4970 E mail CustomerService sae org 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Notes 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE CERTIFICATION TRAINING MANUAL MVAC RECOVER RECOVER RECYCLE OR RECOVER RECYCLE RECHARGE EQUIPMENT CERTIFICATION FORM 1 OF ESTABLISHMENT SEND THIS FORM TO THE EPA REGIONAL OFFICE LISTED UNDER STREET m YOUR STATE OR TERRITORY IM WHICH THE ESTABLISHMENT 15 CITY STATE ZIP CODE LOCATED TELEPHONE NUMBER MAILING ADDRESSES CAN BE 2 FOUND ON THE REVERSE SIDE OF OF EQUIPMENT MANUFACTURER amp MODEL NUM THIS FORM SERIAL NUMBER S YEAR 3 certify that 1 have approved recover recoverlrecycle or recoverrecycle racharge equipment under Section 609 of the Clean Air Act certify that only properly trained and certified technicians operate the equipment and that the information given above is true and correct SIGNATURE OF CVWNER OFERA TOR DATE
53. SI 118 2 Q NO Un z 129 110 151 e Gio XN N N N i 131 111 153 133 112 156 137 114 160 d 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE cross contamination exists It is also important that during the purge process the tank does not become cold since a cold tank of refrigerant will reflect an incorrect pressure read ing Also keep in mind that while pressures higher than those in the charts indicate contamination they do not indicate the type of contamination is it air mixed refrigerants or a com bination of both If tank pressure exceeds the limits in the tables and you are sure that no cross contamination exists the refrigerant can be recycled and reused Just be sure to re perform the check for air process before charging the refrigerant into a system This procedure cannot be used to determine if a mobile A C system has contamination from air or mixed refrigerant 3 What can do to address the problem of air in and get ting in my refrigerant supply How do remove excess air from an A C system Air can be introduced into the refrigerant supply when refrig erant is recovered if there are any leaks in the A C system or the service hoses Inspection of service equipment hoses and connections is important to assure that they are not a leak Source The A C system must be checked for leaks using approved leak detection equipmentand met
54. What About Retrofitting HFC 134a Systems HFC 134a systems are designed and tested only for use with HFC 134a and PAG lubricant There is no published in formation or industry recognized tests to establish system cooling performance system reliability material compat ibility or the potential for chemical damage to the system s lubricant seals and hoses should a substitute refrigerant be installed in an HFC 134a system The U S EPA s Significant New Alternative Policy SNAP Under the Significant New Alternative Policy SNAP in addition to HFC 134a the EPA has accepted some other alternate refrigerants that may be used to retrofit CFC 12 systems However there are no direct drop in replace ments for CFC 12 including HFC 134a and SNAP does not evaluate refrigerants for system performance or durability The only refrigerant on the SNAP list that is approved by vehicle and system OEM is HFC 134a Table 5 lists refrigerants evaluated by the SNAP Tables 6 and 7 list the refrigerant container fittings service fittings and refrigerant labels for the SNAP evaluated CFC 12 replacement refrigerants Currently the refrigerants listed under the SNAP are only intended to be used as replacements for CFC 12 in sys tems originally designed to use CFC 12 The SNAP does not intend that these refrigerants can or should be used as 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE NM 3 TABLE 5 Motor Vehicle Air Conditioning Subs
55. Y WORLDWIDE If a flush solvent is used determine if the solvent is clas sified as a hazardous material Dispose of it in accordance with local state and federal regulations visit www ecar center org ecartour html for more information on specific disposal requirements If you want to power flush a system a safe alternative to solvent flushing is to liquid flush with the refrigerant type used in the system some refrigerant recovery recycling machines provide this feature being sure to run the dis charge refrigerant through an in line filter before allowing it to enter the recovery recycling equipment i Some refrigerant recovery recycling machines used in conjunction with a flushing adaptor kit allow you to use liquid refrigerant to closed loop flush A C systems System Evacuation Before a system is recharged it must be evacuated to re move air and refrigerant It is necessary to use a quality well maintained vacuum pump to perform a worthwhile evacuation But there s a lot more to evacuation than that To thoroughly outgas refrigerant a good vacuum pump whether stand alone or built into a recovery recycling ma chine should be capable of drawing the system down to at least 29 inches of vacuum at facilities located at higher elevations such as Denver the gauge reading will be less A weak or improperly functioning vacuum pump may not be strong enough to achieve complete refrigerant outgas MS CERTIF
56. al problems that result Health and Environmental Effects The Environmental Protection Agency s EPA assessment of the risks from ozone depletion has focused on the fol lowing issues 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE CERTIFICATION TRAINING MANUAL 9 Increases in skin cancers Increases in cataracts 9 Damage to the human immune system 9 Damage to crops Damage to aquatic organisms 9 Increases in ground level ozone 9 Increased global warming Human Health Effects Skin cancer is a serious problem and cases of three dis tinct types have increased because of depletion of the ozone layer Basal and squamous cell skin cancers are the two most common types If detected early these cancers are treatable Even so approximately 196 of cases result in death Malignant melanoma is far less common but sub stantially more harmful Six out of seven skin cancer fatali ties are due to melanoma Cataracts cloud the lens of the eye thus limiting vision Al though cataracts develop for a variety of reasons scientific evidence supports the conclusion that increased exposure to UV radiation can increase the number of people suffer ing from cataracts Increased levels of UV radiation can contribute to the formation of cataracts M S Damage to the immune system is another possible threat Research suggests that exposure to UV radiation weakens the immune system s ability to fend off certain di
57. al system refrigerant leakage during servicing from these reduced emission systems requires improved detection capability of leak detection devices These revisions in SAE J2791 establish a new certification procedure and new leak detection value requirements for certification of electronic probe type leak detectors Published January 2007 SAE J1770 Automotive Refrigerant Recovery Recycling Equipment intended for Use with both R12 and R134a This document establishes the requirements for a single cabinet enclosure having recovery recycle equipment for both R12 and R134a with a common refrigerant circuit It establishes the specifications that assure that the equipment will not cross contaminate refrigerant under normal operating conditions Published October 1995 SAE J1771 Criteria for Refrigerant Identification Equipment for Use with Mobile Air Conditioning Systems This establishes specifications for refrigerant identification equipment used to identify refrigerant purity This was developed due to the refrigerant contamination problems occurring in mobile A C systems and refrigerant supplies Revised November 1998 Recovery Recycle Equipment The mobile air conditioning industry has established SAE performance certification requirements for recovery re cycle equipment and purity requirements for CFC 12 and HFC 134a Equipment certified under ARI 740 which does not have a purity standard cannot be used in the indus try since it
58. an OE part number or designation However the label may not list 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE the lubricant s viscosity You may need to consult another source such as a parts catalog or service information to obtain the lubricant s viscosity rating Recovery only and recovery recycling equipment will sep arate the lubricant during the refrigerant recovery process so properly recycled refrigerant will not contain too much lubricant In general recovery equipment will remove very little if any lubricant from a system It is a design requirement of the equipment that the amount of lubricant removed dur ing recovery must be measurable This is usually but not always indicated by removed oil being collected in a trans parent graduated container If a large quantity of lubricant was removed during recov ery the A C system probably had a lubricant overcharge To replace any lubricant removed during a recovery pro cess use only new lubricant of the type and viscosity speci fied by the vehicle or compressor manufacturer Lubricant removed during recovery must not be reused in the sys tem Used lubricant should be disposed of in accordance with federal state and local requirements visit www ecar center org ecartour html for more information on specific disposal requirements Here is typical recovery machine s oil recovery reservoir It should be emptied before each recovery operation then checked w
59. ant tank is overfilled it may explode To prevent this from occurring when transferring refrigerant into a tank the safe filling level must be controlled by weight and must not exceed 6096 of the tank s gross weight rating 12 NEVER perform service on recovery recycling recharge equipment other than routine maintenance without first consulting authorized service personnel The removal of internal fittings and filters can cause the escape of refrig erant under pressure 13 NEVER perform maintenance or service on recovery recycling recharge equipment with the unit plugged into electric power unless directed otherwise 14 Avoid using extension cords with recovery recycling recharge equipment If this is unavoidable use a minimum length 3 wire No 14 AWG minimum cord with a ground circuit To prevent shock hazards and reduce the risk of fire make sure the extension cord is in good condition not worn or frayed with the ground circuit intact 15 Recovery recycling recharge equipment often contains parts that may produce arcs or sparks Do not use this equip ment near flammable liquids or vapors 16 Fuel injection systems on vehicles contain a service port the same size as one of the CFC 12 A C system service ports Be careful not to attach A C service equipment to a vehicle s fuel injection system Additional health and safety information may be obtained from equipment refrigerant and lubricant manufacturers Refer to their instructio
60. are major leak sources Page 45 Connection and disconnection of service equip ment often results in the release of a small amount of re frigerant at the service ports If the refrigerant released in these circumstances is flammable and there is a source of ignition nearby such as a torch or pilot light on a gas appli ance a fire or explosion could occur Page 45 CAUTION FUEL INJECTION SYSTEMS ON MANY VEHICLES CONTAIN A SERVICE PORT THE SAME SIZE AS ONE OF THE CFC 12 A C SYSTEM SERVICE PORTS BE CAREFUL NOT TO ATTACH A C SERVICE EQUIPMENT TO A VEHICLE S FUEL SYSTEM 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE CERTIFICATION TRAINING MANUAL Refrigerant Recycling and Service Procedures for Mobile Air Conditioning Technicians INTRODUCTION Before the 1990s it was common practice during the ser vice of mobile air conditioning systems to just add refrig erant to leaking systems It was also common practice to vent the entire refrigerant charge to the atmosphere if the refrigeration system required any type of service which involved opening the refrigerant circuit These practices were acceptable because refrigerant was relatively inex pensive and thought to be environmentally benign But knowing what we do today about the role of CFC 12 in the degradation of the earth s protective ozone layer and the potential of global warming venting refrigerants is irresponsible and is not permitted Under the Clean Air Act
61. as such and must be used in accordance with the procedures outlined in the SAE J1628 spec We ve provided an overview of J1628 under Using Electronic Leak Detectors and in the sidebar on page 23 This requires the use of an electronic leak detector certi fied to SAE standard J1627 or J2791 As minimum criteria J1627 electronic leak detectors are capable of identifying leakage rates of 0 5 ounces per year at a distance of 1 4 inch from the leak point M MODEL NO D 340 Design Certified by MET Laboratories inc to meet SAE J1627 for 1 Wy Typical leak detector certification label It shows that this leak detector meets the minimum performance requirements outlined in SAE standard J1627 SAE J1627 leak detector manufacturers provide rating in formation on the detecting capability of their equipment Detectors which have the most sensitive detection levels will help identify smaller leaks Manufacturers service and maintenance procedures must be followed to ensure prop er operation of the equipment SAE standard J2791 covering HFC 134a electronic leak detectors requires improved performance compared to J1627 detectors Detectors certified to this new standard J2791 have the capability of identifying leakage rates as low as 0 15 ounces per year at a distance of 3 8 inch The following charts provide the comparison for different types of leak detection devices and methods
62. been reduced to at least 29 25 inches of vacuum Water boils at 212 F at sea level By reducing the actual sys tem pressure to 27 inches of vacuum to accomplish mois ture removal the entire system would have to be raised to a temperature of 115 F So the bottom line is even the best vacuum pump or re covery recycling machine may not remove moisture by evacuation The best assurance for control of excess mois 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE 2 7 The only way to remove significant moisture from a system is to replace the receiver drier or accumulator Not only that most compressor supplier s war ranties require that the R D or A D be replaced when one of their compressors is being installed ture in the A C system is to install a new receiver drier or accumulator with fresh desiccant Desiccant Failure While we re on the subject of desiccant blend refriger ants that contain HCFC 22 require XH9 desiccant which is generally not available to the mobile A C service in dustry If HCFC 22 is charged into a mobile A C system desiccant damage could occur This can cause blockages within the system Some EPA SNAP accepted substitutes might contain refrigerant s such as HCFC 22 incompatible with the desiccants used in HFC 134a or CFC 12 systems for more information on EPA SNAP accepted alternate refrigerants please refer to pages 42 45 When the refrigerant fittings lines and components are left
63. blishes standards spe cifically for the service of MVACs MVACs are included in the definition of appliances under the stipulations put forth in Section 608 however since their service and repair are regulated under Section 609 they are not subject to the servicing requirements put forth in Section 608 Both regulations require that technicians become certified Technicians who repair or service MVACs must be trained and certified by an EPA approved Section 609 program These programs are specifically designed to cover MVAC refrigerant recovery recycling and charging equipment and procedures in accordance with SAE Standards and Section 609 regulatory requirements After completing a required training program MVAC technicians must pass a test to become certified These tests are different from the Section 608 certification tests Under Section 608 the EPA has established four types of cer tification for technicians that service and repair appliances other than MVACs To be certified technicians must pass a test for the appropriate appliances All training and review classes for Section 608 are voluntary only passing the test is mandatory The four categories of certification are uj Type I Small appliances Type High pressure appliances except small appli ances amp MVACs Type III Low pressure appliances Type IV Universal All appliances except MVACs People who service or repair MVAC like appliances e g farm equip
64. c curs this particulate seeps out and leaves a stain on the outside of the component This stain is then visible when a specific type of UV light is cast upon it Dye manufacturers stress that the purity of the dye and its thermal stability is crucial as the dye will often see A C system high side temperatures of over 250 F then cy cle through evaporator at temperatures in the 30 F to 40 F range The dye should not contain solvents of any kind that could damage system components or diminish the lubricant s properties including viscosity To this effect the SAE has issued standard J2297 to ensure that dyes are tested for HFC 134a system compatibility and to make certain that they will not affect lubricant viscosity when used in proper doses Make sure your dye meets this standard there are some dyes that don t A A S 4 7 4 amp aH 1 Another Tip on Using Electronic Leak Detectors To isolate a suspected leak site in an area where air currents could dissipate leaking refrigerant if possible tape a piece of aluminum foil or plastic wrap around the connection or component Allow some time for possible leaking refrigerant to collect in the plastic wrap or foil Then make a small hole in the foil or wrap at the lowest area possible and place the leak detec tor probe at the hole to check for the leak Lastly most electronic leak detectors require periodic maintenance to function properly Refer to your leak
65. c conversions Use a calculator with this conversion chart or an equivalent for easy reference And watch those decimal points 3 2 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Equipment Inaccuracy The accuracy of shop equipment is a major issue You might have an old recovery recycling recharge machine with a digital scale Its accuracy was never great in its best days For example the GM ACR 4 the first dealer recovery recycling recharge machine for HFC 134a systems had a built in tolerance that was later discovered could go as high as plus minus six ounces a 1996 variation in a two pound system At one time that might have been close to acceptable But since system capacities have dropped and toler ances with them you can encounter a performance problem if you re more than 596 off That digital scale after years of use with little or no maintenance and probably some abuse is likely to have become inaccurate Just because it s calibrated to one ounce or 0 1 does not mean it s accurate to within one ounce or 1 6 ounces There may be a big dif ference between the resolution of the digital display and the actual accuracy of the machine in delivering a charge Some machines have a calibration feature for the scale with special weights but if nothing else you can put 33 pennies on top of the jug and see if the scale can tell the difference 11 pennies weigh one ounce so with 33 there should be an increase in weig
66. d MINI specify a charge tolerance of just plus minus 10 grams 1 3 02 Show Me the Data A typical CFC 12 system required a 3 Ib refrigerant charge but the first HFC 134a systems required only about 1 9 lbs By model year 2000 the industry average charge for a single evaporator system was 1 6 Ibs and in model year 2004 the average charge was down to 1 5 165 As charge volumes have dropped system s tolerances for too much or too little refrigerant have changed as well A system with an incorrect refrigerant charge may suffer unseen problems Low charge can result in uneven tem peratures at the panel outlets and localized evaporator freezing which can reduce system airflow Reduced cool ing can also occur due to a lack of liquid refrigerant enter ing the evaporator Under high cooling loads a portion of the refrigerant may enter the evaporator as a vapor reduc ing system efficiency Test Data Vehicle manufacturers determine refrigerant charge amount by running a specific test under high load condi tions in a climatic test chamber They must consider sev eral factors including accurately measuring the charge amount allowance for some reserve in the system and the effect of too much refrigerant causing a system shutdown via the high pressure compressor clutch cutout switch Table 1 and Chart D on the next page show information on factory charge tests for three different types of refrig erant systems on different vehicle
67. ddressed envelope provided to MACS EIF P O Box 88 Lansdale PA 19446 5 MACS EIF will advise MACS of your test results 6 MACS will advise you of your score and providing that you have attained a passing score will issue a certificate and a wallet sized l D card indicating that you have successfully completed this MACS certification training program 7 Persons not attaining a passing score on the first test will receive one retest at no additional charge If the test was origi nally ordered via phone fax or mail the second test will be sent via U S mail If the original test was ordered online the second test will also be online If a passing score is not attained on the second test the process begins again with a new test purchase Enclosed Test with identification material and declaration to be mailed to scoring facility Postage paid return envelope MACS EIF Important Please note Tests must be returned for scoring within 90 days of the date they are issued MACS assumes no responsibility for tests submitted for scoring after this 90 day period MACS will charge an additional fee for re issuing tests which are lost misplaced or destroyed 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE NM 5 Foreword There is worldwide consensus that chlorofluorocarbons such as the CFC 12 used as a refrigerant in mobile air conditioning systems destroy the stratospheric ozone layer This industry has moved with all possible
68. dout shows an increase in weight from 34 Ibs 4 oz to 34 Ibs 7 oz ant during service The study revealed that electronic read outs may give incorrect readings during service Examples of readings compared to actual amount of refrigerant trans ferred in vapor and liquid form can be found in Table 2 TABLE 2 Refrigerant Transferred Reading vs Actual Amount Equipment Refrigerant Phase Reading Oz 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Actual Refrigerant Amount Diff From Actual Transferred Oz Ww s LH F a N N D N 4 A N A F3 FA J N 4 I N VIAIN FA SE WS N N J V 17 The only service equipment that meets the SAE require ments for charging and removal of refrigerant from a sys tem carries a certification to SAE J2788 With the requirement to service reduced refrigerant charge systems SAE J2788 equipment provides the following mea surement accuracy The equipment must be capable of both indicating and recharging the system to within 15 g 0 50 oz of vehicle manufacturer s specifications If a scale is used in the machine the equipment man ufacturer shall provide a method or service for the technician to check scale accuracy and include any necessary accuracy checking device such as a calibra tion weight s with the machine If you are having a problem with system per
69. dresses hose assembly refrigerant leakage and was published in 2005 This SAE Standard covers hose and hose assemblies intended for conducting liquid and gaseous R134a refrigerant in automotive air conditioning systems The hose shall be designed to minimize permeation of R134a refrigerant contamination of the system and to be functional over a temperature range of 30 C to 125 C Specific construction details are to be agreed upon between user and supplier A hose marked 2064 signifies that it has been coupled tested and has met the requirements of SAE J2064 It is the hose assembly manufacturer s responsibility to see that the assemblies meet the specified acceptance criteria for this specification Service Activities SAE J2196 Service Hose for Automotive Air Conditioning This defines service equipment gauge lines hose emission rates and construction requirements for service hoses Revised November 1998 SAE J2197 HFC 134a Service Hose Fittings for Automotive Air Conditioning Service Equipment To prevent mixing of HFC 134a with other refrigerants a 1 2 inch Acme thread fitting for containers was developed by the Compressed Gas Association CGA This 1 2 inch Acme thread is also required on HFC 134a automotive service equipment Revised March 1997 SAE J2297 Stability and Compatibility Criteria of Fluorescent Refrigerant Leak Detection Dyes for Mobile R134a Air Conditioning Systems This provides requirements for
70. e of 50 psig It will be about 100 psig at 100 F Note Soap bubbles will only identify leaks that are in ex cess of 40 ounces per year compared to the use of a SAE 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE J1627 or J2791 electronic leak detector which can identify leaks with a rate of less than one ounce per year please re fer back to Chart A on page 21 Another Big Reason to Find and Fix Refrigerant Leaks Loss of refrigerant can reduce oil circulation even before the low pressure switch or other sensor shuts down power to the compressor clutch Today s tight clearance compres sors using HFC 134a are tougher to lubricate even with the right PAG oil Compressors that are clutch less can operate until failure of the drive occurs If a vehicle comes into your shop with a failed compres sor and the system is low on refrigerant just replacing the compressor is not going to fix the apparent leak It is im portant to determine if there were multiple leak sources Another leaking system part and loss of refrigerant could have caused the compressor failure Three Questions about Electronic Leak Detectors 1 What conditions can affect the ability of electronic leak detectors to find leaks Dirt and moisture coming in contact with the detector s probe tip can be hindrances when it comes to electron ic leak detection Distance from the probe to the leak site and windy environments also dramatically reduce detec
71. e used any time refrigerant must be removed from a system for any reason Notes 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE to report their inventory pay the difference between the prior year tax rate per pound Each year the floor tax increases 45 cents on each pound of refrigerant in stock Refrigerant recycled on site from mobile A C systems is not taxable The floor stock tax on ozone depleting chemicals is due and payable without assessment or notice on or before June 30 The tax must be deposited together with Form 8109 Federal Tax Coupon at an authorized depository of the Federal Reserve Bank serving the taxpayer s area If a businesses inventory is 399 pounds or less no tax pay ment is required If inventory is 400 pounds or more tax is required on all of the refrigerant the first 399 pounds is not exempted Every person liable for the floor stocks tax must file a return of tax on Form 720 Quarterly Federal Excise Tax Return to which Form 6627 Environmental Taxes is attached by June 30 Note Consult your tax advisor for additional information Imported Used and Refrigerant Since January 1 1996 new CFC refrigerant cannot be im ported However it is permissible to import used or recy cled CFC refrigerant There is no federal requirement that containers of used or recycled refrigerant must be labeled to identify content or purity CFC 12 Supply Future of CFC
72. easing or reducing the system s charge Or there may have been a late change in a component that changes the charge spec and that change was not made on the production line or on the vehicle s A C system information label So unless you have access to the latest service bulletins you may not know about it Sometimes new refrigerant labels are released However the odds that a new refrigerant label was actually attached to the vehicle are pretty remote so checking for bulletins is important including those for the not so new models that you re likely to be working on Please keep in mind that the original charge was approved after testing so if there s a new charge specification it may not improve cooling un der all conditions Also some replacement condensers require a change in sys tem charge spec usually a reduction These units are accom panied by instructions stating the new spec as well as a new label that you are directed to place over the vehicle s original charge spec label But does every tech always read all of the instructions that come in a box with a part And even if so once again will every tech be diligent enough to affix the new label to the system Always be on the lookout for these types of outside the box circumstances Incorrect Calculation of Charge Probably the easiest error to make is calculating pounds to ounces when there s a decimal involved Here s a case his tory from a 93 Chrysler minivan wit
73. ecycled 134 C oed xov m Oo ed ov Poe da 8 Service Equipment HOSES hh 9 Eduibpment 9 Edgtipment ROC AIO de Dan onde eo na de Gens TV Pp EU 9 Other Record Keeping Requirements ass ame RR AREE newer See ee ee Re 9 Further Mobile A C Service Rules and Regulations 0 ccc ccc cc ccc cece eee teen II 10 Regulations Applicable to Vehicle Salvage and or Disposal Facilities 10 Word Recovery only EQUIPMENT oso qc 3 939 3 os CURIE ERU Ae 11 Taxon CFC I2 c HO 11 Imported Used and Recycled Refrigerant 12 12 Supply Future of 12 SystemS n van er doe o dos PR a A o PR oA nn net 12 Service Procedures for Mobile Air Conditioning Systems 13 Maintaining Your Refrigerant Recovery Recycling Recharge Equipment 14 Refrigerant Recovery and Recycling Procedures 00 0 15 Ensure System Integrity 15 Check for Pressure in the System ns 15 The Effect of System Design on the Refrigerant Recovery 5 16 More
74. egistered for MACS certification in REFRIGERANT RECYCLING amp SERVICE PROCEDURES FOR MOBILE AIR CONDI TIONING TECHNICIANS Following are the steps necessary for you to complete the prescribed training The following instructions apply to those technicians taking the MACS training course by mail Those par ticipating in a classroom program should follow the instructions of their trainer proctor Tests given in a classroom setting must be closed book tests The required score for passing these closed book tests is less than that required for passing the open book test Read the instruction manual that came with your recovery recycling service equipment and review the training video if provided Then read this manual cover to cover Re read as necessary to gain full comprehension of the ma terial presented 2 Take the enclosed test The test is an untimed open book test so you may refer to the training manual as often as nec essary to research answers to the questions posed Note however that you must correctly answer a minimum of 21 of the 25 questions to earn certification You must complete the test by yourself without assistance from anyone and submit it for scoring See 4 below 3 Fill out and sign the Identification and Statement of Testing Conditions block on the back of your test Note A reprint charge will be incurred if information provided is not legible 4 Mail your test in the postage paid a
75. eir location It is not required under federal regulations to remove refrigerant from a leaking system However this action CERTIFICATION TRAINING MANUAL may be required under state and local laws It is the technician s responsibility to find out if a more strin gent policy is applicable in their location Service facilities may adopt a policy to not add refrigerant to leaking systems but the policy should be explained to the customer including in the explanation the fact that the policy is not a federal or local governmental requirement Technicians should offer to fix leaks in air conditioning systems It helps protect the environment and conserves refrigerant supplies In addition eliminating the system leakage can prolong the life of the A C system It is not correct however to state or imply that the leak repair is required under federal law Doing so would constitute con sumer fraud It is your responsibility to determine if addi tional regional requirements apply If a customer arrives with refrigerant in their A C system and a technician removes it then the customer declines that any further services be performed the technician must return to the system the refrigerant that was in the system when it ar rived unless the customer agrees to its removal Regulations Applicable to Vehicle Salvage and or Disposal Facilities Vehicle salvage and disposal facilities must remove refrig erants from salvaged or scrapped
76. emical s influence on global warming Fully Halogenated Chlorofluorocarbons ODP GWP CFC 11 1 0 4 680 CFC 12 1 0 10 720 Comparison to HFC 134a ODP GWP HFC 134a 0 1 410 Global Warming Concerns regarding the global warming potential of HFC 134a led the European Union to ban the use of HFC 134a in mobile air conditioning starting in 2011 The global automo tive industry and the U S EPA are evaluating possible use of replacement refrigerants These global concerns regarding the release of refrigerants during the service of mobile A C systems have resulted in revised standards for service procedures and equipment A 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE To reduce refrigerant emissions during service new equip ment and servicing procedures have been developed Ad ditionally improved system designs will result in reduced refrigerant emissions and increased system operating ef ficiencies Field Study Refrigerant Recovery and Reuse Because of ozone depletion industry efforts were directed toward determining if CFCs used in mobile air conditioning systems could be recycled for reuse In the summer of 1988 the EPA with the support of the Mobile Air Conditioning Society Worldwide MACS initiated a sampling program of used refrigerant from 227 vehicles located in four regions of the country The vehicles included both low and high mileage examples ones equipped with properly operating systems as well as ones
77. emoval Many recovery recycling machines have built in five minute wait period after the system is first drawn into a vacuum and if a rise in system pressure is sensed will auto matically repeat the recovery process until the system will remain at a stable vacuum Cautions 1 At no time should an open flame torch be used to heat the accumulator 2 All refrigerant must be removed before opening any of the system s connections More Complete Refrigerant Recovery The amount of refrigerant you can recover from a system depends on how much is in the system of course but also ambient temperature the technique you use and the per formance of the recovery machine itself When you try to draw out the refrigerant the vacuum lowers the tempera tures in the system the oil chills and forms a virtually im penetrable blanket over some of the refrigerant 6 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Engine Pre Heat for Refrigerant Removal Procedure The following procedure will aid in refrigerant removal when the work area is cool and J2210 and J1732 recov ery equipment is being used In general if the work area is warmer than 90 F 32 C this procedure is not required Recovery equipment certified to J2788 and J2810 does not require this pre warming procedure Removal Procedure 1 A C System Controls lt Compressor clutch off e Turn clutch off or remove electrical connection lt Set panel system controls
78. ences in the percentage of refrigerant that s recovered using best techniques versus shortcuts A single pull on a cool morning might remove 6096 of the charge whereas a careful procedure using heat to promote outgassing might remove the over 9096 that is necessary for accurate service Perhaps nothing can demonstrate the facts better than the data shown in the charts below They clearly illustrate the vast difference in the amount of refrigerant that can be re covered from a system at different ambient temperatures and whether or not the system was pre heated during the recovery process Chart A shows that at 50 F ambient without pre heating the system only slightly more than 7096 of the refrigerant is removed on the first recovery attempt It takes three recov ery attempts over 48 hours at this ambient to remove 91 996 of the refrigerant Pre heating even at this 50 F ambient improves recovery removing more than 8096 of the refrig erant With pre heating a second recovery attempt after 24 hours removes more than 9396 of the refrigerant Chart B see next page shows an increase in the amount of refrigerant recovered at the higher ambient temperature of 70 F slightly over 8096 on the first recovery compared to just over 7096 at 50 F Pre heating the A C system by run ning the engine further improves the yield with 87 996 of the refrigerant recovered on the first pull under this condition Refrigerant Recovery Single E
79. ers These refrigerants have not been marketed yet therefore fittings have not been developed Table 7 MVAC Refrigerant Label Colors To comply with the conditions on the use of motor vehicle refrigerants a detailed label must be applied that features a unique background color This table summarizes the col ors chosen for the refrigerants listed as of June 3 1997 The information required for each label is listed in EPA s fact sheet titled Choosing and Using Alternative Refrigerants S for Motor Vehicle Air Conditioning available from EPA s world wide web site and from the Stratospheric Ozone Ho tine at 800 296 1996 Se 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE replacements for HFC 134a However in the future the EPA may identify replacement refrigerants for HFC 134a and vehicle and A C system manufacturers will decide if these refrigerants meet their approval Current mobile A C systems are not designed to use blend refrigerants Blends refrigerants may provide cooling performance when initially charged However each refrigerant in a blend has a different pressure temperature relationship and dif ferent leakage rates through the A C system hoses Blends can separate while in use and a leak in a system can allow one component of the blend to escape at a faster rate This partial leakage can change the entire refrigerant mixture and cause system operating problems A Word on Flammable Refr
80. eview the following Page 22 To prevent contamination leak detection must only be done with the refrigerant that is specified for the system Do not attempt to use shop air for leak detection purposes Page 23 Leaktesting of the evaporator core is a challeng ing task Page 28 A system with an incorrect refrigerant charge may suffer unseen problems Accumulator or Receiver Drier The accumulator or receiver drier is important for control ling moisture in the A C system and in the event of a me chanical failure can become a collection point for foreign material which could then be circulated in the system and cause further system damage For more details regarding replacement of this component see Page 5 A C systems contain desiccant material Desic cant which absorbs moisture in the system is located in the receiver drier or accumulator or are integral in a car tridge or bag with the condenser Page 16 To remove as much of the refrigerant as possible during the recovery process systems equipped with orifice tubes and accumulators require more time than systems equipped with expansion valves receiver driers Page 28 The only way to remove significant moisture from a system is to replace the receiver drier or accumulator Flexible Hose Hose Coupling Hoses can develop leaks at hose coupling assemblies due to mechanical rub through In addition to hose failure all system couplings or attachments
81. f December 18 2000 REFRIGERANT CONTACT HIGH SIDE SERVICE PORT LOW SIDE SERVICE PORT 30 LB CYLINDERS SMALL CANS Diameter Pitch Thread Diameter Pitch Thread Diameter Pitch Thread Diameter Pitch Thread inches threads inch Direction inches threads inch Direction inches threads inch Direction inches threads inch Direction 6 16 Right 7 16 20 Right 7 16 20 Right 7 16 20 Right 1987 9 9 9 9 multiple LER 1987 HFC i34a 134a multiple qucd connect 16 Right 16Acme Right Technical Freeze 12 Chemical 7 16 8 16 Right Right 6 16 Right 800 527 0885 Free Zonal Refrigerant RB 276 Gases 8 16 Right 9 16 Right 9 16 Right 6 16 888 373 3066 Hot Shot IGOR ES Right Right Right 800 357 4062 Eu E McMullen Oil CUM Products Inc 6 16 7 16 Right 14mm cu 800 669 5730 poung GHG X4 1 Autafront EF E Eu ms 4mm 800 382 9006 GHG P not yet developed Ikon 12 Ikon Ikon A 555 345 2707 IO FRIGC Intercool 12 800 555 1442 quick connect different from HFC 134a quick connect different from HFC 134a 8 16 20 Left 7 16 20 Left RS 24 Refrigerant quick connect different from HFC 134a quick connect different from HFC 134a and quick connect different from HFC 134a quick connect different from HFC 134a Solutions Ltd and FRIGC FR 12 FRIGC FR 12 and FRIGC FR 12 and FRIGC FR 12 P Wr e
82. f high quality flexible hose mate rial and improved pipe connections reduce system refrigerant loss 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Appendix SAE Standards Applicable to Mobile System Service Since the first SAE document J513 in January 1936 which conforms to ANSI B70 1974 SAE refrigeration flare fittings have been an industry standard In April 1953 SAE J639 provided standards for system service access fittings cur rently used by the automotive and commercial industry To prevent mis connections SAE J639 was revised in the 705 to provide different size system service connections on CFC 12 mobile A C systems The use of different high and low refrigeration service access fittings are not used by the commercial industry When the mobile industry changed refrigerants from CFC 12 to HFC 134a new unique quick couple service fittings were developed to reduce venting and possible mixing of refrigerants during service of mobile A C systems New unique quick couple service fittings have been developed for R744 carbon dioxide and HFC 152a mobile A C sys tems and are identified in J639 The mobile air conditioning industry established replace ment refrigerant criteria resulting in new SAE documents The industry EPA field study of mobile A C systems identi fied what level of contamination could be expected from used CFC 12 refrigerant and established equipment require ments and the purity levels for
83. fication will be required for techni cians servicing R744 systems HFC 152a Systems HFC 152a is another refrigerant that can meet the Europe an Community s requirements HFC 152a has a lower GWP value than HFC 134a but a higher GWP value than 744 HFC 152a has similar operating pressures to HFC 134a However HFC 152a is flammable so its use would also re quire system design features to address vehicle occupant and service personnel safety Two types of HFC 152a systems have so far been demon strated the direct expansion type and the secondary loop type The direct expansion type is just like an HFC 134a sys tem except that to address the flammability issue system safety features are required The secondary loop type in corporates a direct expansion refrigerant circuit located in the engine compartment with a chiller that cools a non flammable liquid The non flammable liquid is circulated to a cooling coil that replaces the evaporator This provides isolation between the flammable refrigerant and the pas senger compartment As with R744 new service equipment procedures training and possible certification will be required for technicians servicing HFC 152a systems Other Alternative Refrigerants New chemicals being developed as replacement refriger ants with low GWP ratings may also enter the marketplace The future mobile A C systems in which they are intended for use will be specifically designed to use these ne
84. fittings have to be designed to leak far less Page 42 As determined by the vehicle or system manu facturer additional retrofit requirements and recommen dations may include the installation of new o rings and or seals new desiccant a different lubricant replacement of refrigerant controls increased condenser capacity and other modifications Page 42 There is no published information or industry recognized tests to establish system cooling performance system reliability material compatibility or the potential for chemical damage to the system s lubricant seals and hoses should a substitute refrigerant be installed in an HFC 134a system Page 51 SAE J1662 Compatibility of Retrofit Refriger ants with Air Conditioning Materials Seals hoses and O rings used in CFC 12 systems may not be compatible with some alternate refrigerants and could break down causing system failures Service Ports Service port fittings will develop leaks from normal service operations and replacement of service port caps is a criti cal but often overlooked step in preventing leaks Follow ing are pertinent references Page 15 As a first step in service always perform a vi sual inspection to spot obvious problems Since the service port caps serve as the primary seal for the service ports make sure that each service port in the system has a cap installed and that the caps seals are not damaged Missing or damaged service port caps
85. for Mobile Air Conditioning Systems The purpose of this SAE Standard is to establish the specific minimum equipment performance requirements for recovery and recycling of HFC 134a that has been directly removed from and is intended for reuse in mobile air conditioning A C systems It also is intended to establish requirements for equipment used to recharge HFC 134a to an accuracy level that meets Section 9 of this document and SAE J2099 The requirements apply to the following types of service equipment and their specific applications This standard supersedes the requirements of SAE J2210 to reduce refrigerant emissions during servicing and provides requirements for charging refrigerant into mobile air conditioning systems This SAE Standardisto establish the specific minimum equipment requirements for the recovery recycling of HFC 134a that has been directly removed from and is intended for reuse in mobile air conditioning systems and recovery recycling and system recharging of recycled or virgin HFC 134a Establishing such specifications will ensure that system operation with recycled HFC 134a will provide the same level of performance and durability as new refrigerant Published December 2006 SAE J2810 HFC 134a R134a Refrigerant Recovery Equipment for Mobile Automotive Air Conditioning Systems The purpose of this SAE Standard is to provide minimum performance and operating feature requirements for the recovery of HFC 134a R134a
86. formance or high system operating pressure you may want to check if the charging equipment is transferring the correct amount of refrigerant Test Procedure for Refrigerant Transfer Using a separate container and an external calibrated scale 1 Evacuate and weigh the container on the calibrated scale and record the container weight 2 Transfer an amount of refrigerant from the charging equipment 3 Check the container weight and determine if the weight has increased by the amount you transferred from the charging equipment e f the container weight step 1 has not increased by the amount transferred step 2 then the measuring device on the charging equipment may be in error Not Accounting for the Refrigerant Inside the Service Hoses Charge the system with the specified amount of refrig erant allowing for the capacity of the charging hoses A typical six foot service hose holds approximately two ounces of refrigerant The use of very long service hoses can cause a system to receive an overcharge if procedures are not followed that take hose length into consideration Some charging equipment is programmable to allow for different hose lengths which should assure an accurate charge Refer to your machine s instruction manual for more information Technician Doesn t Accept the Specs It s amazing how many shops refuse to accept the factory spec even if there s no bulletin to the contrary Or some how they have acquired
87. frigerants are sometimes mixed with CFC 12 HFC 134a or HCFC refrigerants in an A C system This is an other reason why the use of a refrigerant identifier should be incorporated into all mobile A C refrigeration system service procedures The identifier will indicate the pres ence of the flammable refrigerant WARNING REMOVAL AND HANDLING OF FLAMMABLE RE FRIGERANTS MAY BE DANGEROUS Fuel System Fittings CAUTION FUEL INJECTION SYSTEMS ON MANY VEHICLES CONTAIN A SERVICE PORT THE SAME SIZE AS ONE OF THE CFC 12 A C SYSTEM SERVICE PORTS BE CAREFUL NOT TO ATTACH A C SERVICE EQUIPMENT TO A VEHICLE S FUEL SYSTEM 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE SERVICING OF FUTURE MOBILE AIR CONDITIONING SYSTEMS As the world becomes more concerned about the global environment the type and amount of refrigerant use in mobile air conditioning systems has resulted in system de sign changes new service procedures and equipment to reduce lifetime emissions The global automotive industry and the U S EPA are evalu ating containment of refrigerants and the possibility of new replacement refrigerants that will affect the service of future systems European Phase Out of HFC 134a Starting in 2011 the A C systems in vehicles sold in Europe must use a refrigerant that has a Global Warming Potential GWP of less than 150 Automobile manufacturers must meet this requirement for that marketplace and there is the possibility that vehicle
88. h cut out switch to inhibit compressor clutch operation and or depending on the circumstance possibly cause damage to system components due to overpressure conditions In sys tems that use the low side pressure to control the evaporator such as pressure cycling or variable displacement compres sors a system having excess air in the refrigerant will have a loss of performance Generally speaking having more than about 2 air by weight in the refrigerant charge can start to cause problems with system operation With some systems every percent age point that air contamination exceeds 296 can lead to a one degree F increase in evaporator outlet temperature For example a system containing 1096 air may be blowing eight degrees warmer than it should at the dash outlets even if ev erything else in the system is functioning perfectly The bottom line is that the maximum acceptable amount of air contamination is generally considered to be no more than 296 2 How can technicians determine if refrigerant contains too much air The only way to determine the amount of air contained in refrigerant is to use a refrigerant identifier To determine if a container of refrigerant has excess air the following approach can be used The container must be kept at a stable temperature for several hours before taking the readings In a busy shop atmosphere this is not always possible Contamination can also be caused by mixed refriger ants
89. h a 3 13 lb spec An in experienced tech charged 3 Ibs 13 ounces 3 Ibs x 16 for a total of 48 ounces plus 13 equals 61 ounces into the system The correct amount is 50 ounces 0 13 Ib x 16 ounces is 2 08 ounces Add in 48 ounces 3 lbs x 16 and the total is 50 08 ounces So the results were about an 11 ounce overcharge high discharge pressures and a puzzled technician Or the reverse could apply A label in ounces and a machine with a display in pounds with the decimal In this case di vide the total number of ounces by 16 Example 50 divided by 16 equals 3 13 Ibs If your machine display is calibrated to a single decimal place round off 3 13 Ibs to 3 2 Ibs 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE trm TEIL ai 7 Li RTE LME Maso 1 auam This machine is displaying the refrigerant charge amount in pounds and ounces Unfortunately the label on every vehicle you service won t list the spec this way so calculations will be needed an easy place to make a mis take Some machines allow you to change the display units but how many techs do so every time they can or should Still another calculation issue grams and kilograms when you have a machine in pounds and or ounces There are 28 4 grams per ounce and 2 2046 pounds per kilogram The numbers are usually rounded off on spec labels and if so you won t have to worry about that level of accuracy Land Rover
90. hen recovery is completed to see how much if any oil was removed from the system dur ing recovery If oil was removed that same quantity of fresh new oil of the type the system requires must be reinstalled in the system before it is put back into operation Notes 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Notes 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE CERTIFICATION TRAINING MANUAL Best Service Practices for Mobile A C System Systems Sources of Refrigerant Emissions Motor vehicle air conditioning systems can release refriger ant into the atmosphere in a number of ways Leaks from system part failures and seepage which occur when a leak is not repaired and the system is re charged or topped off Refrigerant released during various service proce dures Refrigerant released from service equipment mani fold gauges and equipment hoses When using small cans to charge a system refrigerant remaining in the can is likely to ultimately be vented The refrigerant remaining in larger 30 pound dispos able containers that has not been recovered is also sometimes vented when they are scrapped Checking Mobile A C Systems for Leaks The EPA and MACS recommend that leaking systems should be repaired To pinpoint leaks in mobile A C systems MACS recommends using the SAE J1628 service procedure Your electronic leak detector s must be certified to meet the SAE spec the detector should be labeled
91. his is a safety measure to pre vent possible direct reuse of non recycled refrigerant Like recovery recycling machines recovery only equip ment must be equipped with a device to allow the opera tor to determine how much lubricant was removed during the recovery process Tax on CFC 12 On January 1 of each year businesses with an inventory or floor stock of 400 pounds of CFC 12 or more are required Important Dates Jan 1 1992 Since this date containment and re cycling of CFC 12 and HCFC refrigerants has been required Nov 15 1992 Since this date sales of containers of CFCs under 20 pounds to anyone other than certi fied Section 609 technicians has been prohibited Nov 14 1994 Since this date the sale of ozone depleting refrigerants in any size container is re stricted to certified technicians July 1995 Since this date any CFC 12 mobile air conditioning system that is converted retrofitted to use an EPA accepted alternate refrigerant must have installed the appropriate unique service fit tings and label listed for that refrigerant Nov 15 1995 Since this date recovery of all mo bile A C system refrigerants has been required It must be noted that the above regulations apply no matter where a system is undergoing service wheth er itbein a shop or at an off site location such asa farm field construction site etc Approved recovery only or recovery recycling equipment can and must b
92. hods After performing refrigerant identification the refrigerant must be recovered from the system using approved and properly maintained refrigerant recovery recovery recycling equipment All system leaks if any must be repaired After all refrigeration system service is completed the system must be properly evacuated to a deep vacuum to en sure that all air is removed Short cutting evacuation or failing to purge air from the recovered recycled refrigerant are two of the most common causes for air to exist in refrigerant and A C systems Others are improperly operating or maintained recov ery recovery recycling equipment and vacuum pumps in need of oil changes and or other maintenance MM ONLY RET IBGEEANT TTWIH QRIEQUVALENT OR Liz FYETE WELL BE M5 z Properly operating recycling equipment used in accordance with its manufacturer s instructions will remove excess air from refrigerant ensure that the maximum allowable amount of air in recycled refrigerant is not exceeded and provide recy cled refrigerant that is ready for use Mixed Cross contaminated Refrigerant When a vehicle arrives at your shop for A C service try to determine if you might be about to work on a contaminated system Ask the customer questions about work that may have previously been done and especially what may have previously been charged into the system You might find it helpful to u
93. ht of at least 0 1 or two ounces up to 0 2 Ib or three ounces New recovery recycling charging equipment meeting SAE J2788 certification will provide more accurate refrigerant removal and charging measurements and provide a meth od for calibration of the scale SAE had not established any requirements covering the ac curate measurement of recovered and charged refrigerant when servicing mobile air conditioning systems prior to SAE J2788 During industry studies it was determined that an accuracy problem can exist when transferring refriger yc IZO A TIIONNA Tr WIN N N m M m LIE ISAT IJIN NALIN NI NAAN A N N LINX 33 pennies weigh three ounces and most shops can come up with them They can be used to check the scale on your recharge machine Place them on top of the refrigerant tank and check the scale reading on the machine s readout If the scale is working properly within tolerance the scale reading should show an increase in weight of at least 0 1 Ib or two ounces up to 0 2 Ib or three ounces If this does not happen the scale needs either calibration or replacement Anything else is not accurate enough for charging today s tight tolerance systems As you can see the scale on this recovery recycling recharge machine is dead on With 33 pennies placed on top of its refrigerant tank its rea
94. i PRINT TITLE MVAC RECOVER RECOVER RECYCLE OR RECOVER RECYCLE RECHARGE EQUIPMENT CERTIFICATION FORM INSTRUCTIONS Motor vehicle refrigerant recover recover recycle or recover recycle recharge equipment must be acquired by January 1 1992 and certified t EPA on or before January 1 1993 under Section 609 of the Clean Air Act To certify your equipment please complete the above form according to the following instructions and mail to the appropriate EPA region based on where your establishment is located 1 Please provide the name address and telephone number of the establishment where the equipment is located 2 Please provide the name brand model number year and serial number s of the equipment acquired for use at the above establishment 3 The certification statement must be signed by the person who has acquired the equipment the person may be the owner of the establishment or another responsible officer The person who signs is certifying that they have acquired the equipment that each individual authorized to use the equipment is propery trained and certified and that the information provided is true and correct 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE 5 3 E mu CERTIFICATION TRAINING MANUAL EPA REGIONAL OFFICES Send your form to the EPA office listed under the state or territory in which the establishment is located Connecticut Maine Massachusetts New Hampshire Rhode Island Verm
95. igerants Replacement refrigerants which are or can become flam mable have been sold for use in mobile A C systems Current mobile A C systems are not designed to use flam mable refrigerants and using a flammable refrigerant as a replacement for CFC 12 is prohibited by federal law The use of flammable refrigerant to replace any mobile A C system refrigerant is also currently illegal in the following states Arizona Arkansas Connecticut Florida Idaho Indiana lowa Kansas Louisiana Maryland Montana Nebraska North Dakota Oklahoma Texas Utah Virginia Washing ton and Wisconsin as well as in the District of Columbia Caution should be taken before working on any system suspected of containing flammable refrigerant some elec Notes NM 3 tronic leak detectors could become an ignition source if being used to find leaks in a system containing flammable refrigerant components inside many recovery recycling machines can also serve as a possible ignition source if the equipment is being used to recover flammable refrigerant Either of these situations could result in a fire or explosion Connection and disconnection of service equipment of ten results in the release of a small amount of refrigerant at the service ports If the refrigerant released in these cir cumstances is flammable and there is a source of ignition nearby such as a torch or pilot light on a gas appliance a fire or explosion could occur Flammable re
96. ing equipment manufac tured or imported after January 2008 must be certified to J2788 requirements Also in 2007 recovery only equipment standard SAE J1732 was superseded by SAE J2810 The new J2810 equipment provides more complete refrigerant recovery New recov ery only equipment manufactured or imported after Oct 31 2008 must be certified to J2810 Purity of Recycled CFC 12 The SAE J1991 standard of purity for on site recycled CFC 12 states that the refrigerant shall not exceed the following levels of contaminants Recycling vs Reclaiming Recycling versus reclaiming refrigerant there is a difference Recycled refrigerant is that which has been processed on site at a service facility using au tomotive recycling equipment certified to the appropriate SAE J standard Reclaimed refrigerant is that which has been sent to an EPA listed reclamation facility where it is processed and returned to a state which meets the appropriate ARI 700 specification The standards of purity for reclaimed refrigerant are much higher than those for recycled refriger ant Please Note Recovery recycling equipment is not designed to recycle or separate contaminated refrigerants Contaminated or unknown refrigerant must be removed from a system using dedicated recov ery only equipment and properly disposed of Under federal law contaminated refrigerant can not be vented Moisture 15 Parts Per Million PPM by weight Oil
97. k detection must only be done with the refrigerant that is specified for the system Do not attempt to use shop air for leak detection purposes Shop air may introduce air moisture and other contami nants to the system The use of other gases under high pressure such as nitrogen can result in damage to the A C system for example it may cause an evaporator to rup ture Also since soap bubbles will not detect small leaks there is no detection equipment to identify a small leak when using air or nitrogen for leak checking Also using another refrigerant like HCFC 22 could cause chemical damage to system components such as the des iccant material Since evacuation of the system may not remove all the HCFC 22 this can further result in seal hose and lubricant damage The SAE J1628 procedure does not require a fully charged A C system If the system has only a few ounces of refriger ant and at least 50 psig pressure at 59 F that is sufficient to check for a leak This pressure will be higher with the same amount of refrigerant when the working area temperatures are warmer If the system is completely empty it will be necessary to add some refrigerant to the system in order to use an elec tronic leak detector Only a few ounces about 10 to 1596 of the total system charge is enough to obtain a minimum system pressure With this limited amount of refrigerant you can determine if the system has a leak but you cannot
98. l to CFC 12 systems Some of these changes included new hose and seal materials compatible with HFC 134a and the lubricants used with it The new hoses and seal designs also reduced leakage The most noticeable change however is increased con denser capacity and increased airflow to reduce system pressures at low speed operation and city traffic conditions In general condenser performance for HFC 134a systems has been increased by approximately 3096 over that of CFC 12 systems which resulted in comparable performance HFC 134a systems also require a new desiccant material Desiccant which absorbs moisture in the system is lo cated in the receiver drier or accumulator or integral in a cartridge or bag with the condenser CFC 12 systems used XH5 desiccant HFC 134a systems re quire XH7 desiccant Today when a receiver drier or accu mulator is being replaced it should contain XH7 desiccant because it is compatible with both CFC 12 and HFC 134a HFC 134a does not provide the same level of lubricant cir culation as CFC 12 so it is very important that the proper lubricant be used in HFC 134a systems The industry is Oz H 4 The condensers used in HFC 134a systems are more efficient than the ones that were used in CFC 12 systems The 3 8 inch tube and fin condenser shown on the left is an example of the type that was used for many years in CFC 12 systems The parallel flow multi flow condenser on
99. labels are very good in that they give grams and ounces and make it clear which specification applies to front only and also which apply to front rear systems gr ma E x Pa ED ro LAND ROVER Ain 7 wi 25g 25 R134e cic 9009 50g 180ml 327 207 6 9 Moz 11500 50g 40 202 5 3 fos CAUTION Lr EE GA Apo ANA rene gt SAE LAND ROVER Fd 419 PHOLANG These refrigerant labels are typical of those used on two different Land Rover vehicles They give the refrigerant capacity in grams and ounces for both front only systems half vehicle silhouette and front rear systems full ve hicle silhouette and the plus minus tolerance both in grams and ounces Notice that the one for a larger system has a plus minus tolerance of 50 g grams whereas the other for a smaller system has a tolerance of 25 g Many specifications use 25 or 50 g instead of the more precise 28 4 grams per ounce for the plus minus tolerance If you re working in ounces the bottom label s front system would get a charge in the range of 30 34 ounces Volkswagen uses grams so if you re converting to ounces divide by 28 4 Example 750 grams equals 26 4 ounces just under 26 1 2 ounces and the tolerance is plus no minus 50 grams which equals 1 76 ounces just over 1 3 4 ounces So the precise range is
100. list html Used Refrigerant from Non mobile Sources CFC 12 and HFC 134a are also used in residential and com mercial refrigeration systems such as refrigerators wa ter chillers and central cooling systems Many different contaminants and acids may be present in refrigerant re covered from these systems Automotive type recovery recycling equipment will not remove these contaminants Refrigerant which contains acids and other contaminants as well as possibly mixed refrigerants will cause serious problems if it is used in a mobile A C system Refrigerant from non mobile sources should not be used un less it has been purchased from a reclamation center which can certify that the refrigerant meets ARI 700 specifications Purity of New HFC 134a In 2006 both the SAE and the ARI issued more stringent standards concerning the purity of new HFC 134a SAE J2776 and ARI 700 2006 To meet the ARI 700 2006 and SAE J2776 purity require ments volatile impurities shall not exceed 40 parts per million ppm These impurities cannot be identified in the field and the purity information is not normally part of the refrigerant s Material Safety Data Sheet MSDS These impurities have been identified to potentially result in A C system problems and health issues Refrigerant meeting SAE J2776 will have a label on the car ton and container stating Meets SAE J2776 purity stan dard Containers will have 1 2 inch Acme fittings
101. lize then re perform the check to con firm if there is still excess air remaining in the tank Remember The information in the tables is only reliable if the tank has been kept at a stable temperature for several hours before the readings are taken has been kept out of direct sunlight contains some liquid refrigerant and no refrigerant You can use the recovery recycling recharge machine air purge valve to purge excess air from recycled refrigerant Let the air out and watch the pressure gauge on the machines panel When the gauge reading reaches the appropri ate number in the table based on the ambient temperature close the purge valve The recycled refrigerant now does not contain an excessive amount of air and can be reused to recharge an A C system TABLE 3 Maximum Allowable Container Pressure Recycled CFC 12 Temp F PSI PSI OQ Un N N N NO N N D UJ N O Temp F PSI Temp F PSI OV S UJ N N N OQ Co Un NO NIN UJ NO UJ A A N Temp F Co Ui N UJ NO NO NO NO A PSI 102 03 05 7 108 NO i A PSI Temp F P
102. ment and other off road vehicles can choose to be certified by either the Section 609 program or un der Section 608 Type II However due to the similarities between MVAC and MVAC like appliances the EPA recom mends that technicians servicing MVAC like appliances consider certification under Section 609 Note While buses using CFC 12 are MVACs buses and other vehicles using HCFC 22 as refrigerant are not classified as MVACSs or MVAC like appliances but rather as high pres sure equipment covered under Type of the Section 608 test Certification under Section 608 is also required to ser vice cargo refrigeration equipment Mobile A C Service Equipment Certification Operation and Refrigerant Purity The SAE Interior Climate Control Standards Committee de veloped documents containing the procedures to be used for proper handling and use of CFC 12 and HFC 134a in mo bile A C systems The documents include CFC 12 SAE Documents SAE J1989 Service Procedures SAE J1990 Specifications for Recovery Recycling Equipment SAE J1991 Standard of Purity 608 vs 609 MVAC 609 Passenger Cars and Trucks Military vehicles passenger if R 22 then 608 MVAC like 609 Appliance 608 Trains Ei m Refrigerated Trailers Do you need Section 609 Certification Section 608 Certification or maybe both This chart will tell you which type s you need 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWI
103. mobile A C systems prior to about 1992 Leaks and other releases allow them to en ter the atmosphere stances which Deplete the Ozone Layer This landmark international agreement is designed to control the produc tion and consumption of certain chlorofluorocarbon and halon compounds In the 1980s mobile air conditioning systems used CFC 12 refrigerant With the advent of the Montreal Protocol the industry changed to HFC 134a In 1990 the U S Clean Air Act addressed the refrigerants used in mobile air condi tioning systems CFC 12 has both an ozone depleting and Global Warming Potential GWP HFC 134a is not ozone depleting but is considered to have global warming potential By late 1994 all new mobile air conditioning systems produced in the United States used HFC 134a Blend refrigerants that were listed as acceptable by the EPA for servicing mobile air con ditioning systems are covered by the venting prohibition and like CFC 12 and HFC 134a cannot be released into the atmosphere 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE sphere CFCs were used as blowing agents in plastic foam products cushioning insulation and packaging as refrig erants as solvents as sterilants and in aerosol applications Additionally halons are used as fire extinguishing agents A concern identified under the Montreal Protocol was that a significant reduction in ozone in the upper atmosphere could result in long term increases
104. mobile A C systems Salvage and disposal facilities that have certified recovery equipment can recover refrigerant at their facility and also move the equipment to other salvage and or disposal fa cilities to recover refrigerant If CFC 12 this refrigerant can be sold to technicians certi fied under section 609 If HFC 134a it can be sold to any one wishing to purchase it The salvage employee does not have to be certified to perform this operation However an uncertified person working for consideration cannot charge these refrigerants into a mobile A C system and the refrigerants must be recycled before reuse ta 1 EM Refrigerant must be recovered from the A C systems in scrapped vehicles be fore final disposal 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Section 609 certified technicians that are not employed by the salvage or disposal facility can remove CFC 12 and HFC 134a from mobile A C systems at the salvage and or dis posal facility The refrigerant recovered must be recycled before reuse in other vehicles Since there is no require ment to identify the purity of this refrigerant or label tanks as containing refrigerant removed from vehicles at these facilities it is important to keep in mind that any refriger ant removed from vehicles at salvage and disposal facilities can be contaminated Salvage and disposal facilities must keep records docu menting when and if someone not directly employed by
105. ms For the Integral Condenser RD the high pressure change from 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE M 5 Ms CERTIFICATION TRAINING MANUAL System Pressure vx Refrigerant Charge E p x Tis e 1 sd 1 CEE BELPER ELE DEP i i d a ewes 7 ee iia ii 17 8 1H TTE a nn es 142 20B 22 224 24 mintegi Lew BTE High Chart E Lew OT System Charge Curve 5 3 5 Panal Outlet Degrees F Tormparabure T 55 un 58 oO JE s M A 16 0 18 0 20 0 a Low Side PSIG mM 837 58 40 22 0 24 0 25 0 25 0 Dunces Rissa Dasrqueraligte High Side Pressure Chart F 18 to 24 ounces 6 ounce change is only 9 psig 230 239 and low side is less than 1 psig The TXV system pressure change on the high side from 24 to 30 ounces 6 ounce change is 15 psig 295 310 and low side is 3 psig 61 58 The OT system pressure change on the high side from 22 to 28 ounces 6 ounce change is 23 psig 225 248 and low side is 5 psig 58 63 Chart F shows the effect of reduced refrigerant charge on the compressor discharge temperature of a factory
106. n manuals and Material Safety Data Sheets 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE ER CLDTIEI CATICYNITDAINIINIC NAANILIA 2 V N LN CERTIFICATION TRAINING MANUAL Maintaining Your Refrigerant Recovery Recycling Recharge Equipment Recovery recycling recharge equipment should be checked frequently to ensure that no leaks exist within the internal refrigerant flow circuits as well as the external hoses and seals Filters driers must also be replaced in ac cordance with the machine manufacturer s specifications check the equipment manual for filter location Regular maintenance of your recovery recycling recharge ma chines should help to ensure that the SAE standards of pu rity for recycled refrigerant are met The seals on service equipment hoses must be frequently inspected for dam age and replaced when necessary This shows a comparison between a new seal left and a used one that is swelled and distorted right R R R machine internal plumbing must be periodically checked to make sure R R R machine filters driers must be replaced in accordance with the ma no leaks are present chine manufacturer s recommendations 14 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Refrigerant Recovery and Recyding Procedures Before You Begin Refrigerant Identifiers A refrigerant identifier can help alert you to air condition ing system refrigerant contamination problems
107. n the System It would make no sense to attempt refrigerant recovery from a system that contains no refrigerant Because of this always check to see if the system has pressure by installing Before connecting service equipment always perform a visual inspection of the A C system to spot any obvious problems a The caps are the service ports primary seal against refrigerant leakage Always make sure that every service port has one in place a pressure gauge on a system service port before starting a recovery process If a system contains no pressure it is a safe assumption that the refrigerant has leaked out and one of your first steps in service should be trying to track down a leak or leaks in the system If a system has some pressure but contains an unknown amount of refrigerant some additional refrigerant can be added to check the system s operation It is advisable to provide the best system diagnosis that the remaining refrig erant be recovered and the factory charge amount of refrig erant be added If further inspection reveals a leak but the customer declines to have repairs performed the following options can be considered under current federal law Option 1 Under Section 609 the service facility can charge the customer for the inspection and added re frigerant and return their vehicle to them there is no EPA requirement that refrigerant must be removed from a leaking system 2008 MOBIL
108. nformation in the fol lowing bullet points must be mailed to the EPA regional office for the state or territory in which the establishment is located see pages 53 and 54 Name address and telephone number of the estab lishment where the recovery recycling equipment is located Name brand model number year and serial number s of the equipment acquired for use at the above es tablishment The above information can be submitted on a plain sheet of paper or can be submitted on a special form the EPA pro vides for this purpose A copy of this form is provided in the back of this manual You may photocopy it for your use The person responsible for the equipment must sign the form The person who signs is certifying that they are re sponsible for the equipment that each individual assigned to use the equipment is properly trained and certified and that the information provided is true and correct The repair facility is required to file this certification only one time The shop owner should keep a copy of the equipment certification on file Other Record Keeping Requirements Note All records listed below must be retained for a period of three years As mentioned above any person who owns approved refrigerant recovery recycling equipment and pro vides service for a monetary value must have records demonstrating that all persons assigned to operate the equipment are currently certified Any person who owns approved refrige
109. nt identifier is the best tool to use to obtain a reading on the amount of air that might be in recycled refrigerant To measure the refrigerant liquid temperature attach a calibrated thermometer to and measure the temperature of the lower one half of the refrigerant container s outer surface Or shoot an infrared thermometer at the lower one half of the refrigerant container to obtain a reading Using only the air temperature reading in the vicinity of the refrigerant container can result in incorrect refrigerant tem perature information 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Compare the pressure gauge and temperature readings with the limits found in Tables 3 and 4 Use the figures in Table 3 for CFC 12 and the figures in Table 4 for HFC 134a If tank pressure is below the figure listed in the table and the refrigerant has been recycled the refrigerant does not contain an excessive amount of air If tank pressure is high that listed in the table for the ambient temperature and its contents have been recycled it is advisable to use a refrigerant identifier and confirm if the high pressure is due to excess air or cross contamination If it s determined to be excess air slowly vent purge the air from the tank Continue purging until tank pressure is below that shown in the table As the purge process is performed the contain er will cool and the tank pressure will decrease Allow the temperature to stabi
110. o CFC 12 systems Some of these changes included new hose and seal materials compatible with HFC 134a and the lubricants used with it The new hoses and seal designs also reduced leakage Page 13 To help avoid skin contact mineral oil should be used to coat o rings and seals prior to installation Also since PAG lubricants absorb moisture using mineral oil re duces the potential for fitting corrosion Page 14 Recovery recycling recharge equipment should be checked frequently to ensure that no leaks exist within the internal refrigerant flow circuits as well as the external hoses and seals O rings and seals continued next page 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE 5 IT O rings and seals continued Page 22 Also using another refrigerant like HCFC 22 could cause chemical damage to system components such as the desiccant material Since evacuation of the sys tem may not remove all the HCFC 22 this can further result in seal hose and lubricant damage Page 26 This residual solvent can dilute the lubricant which can lead to inadequate compressor lubrication and possible subsequent compressor failure It could also pos sibly affect the chemical stability of the refrigerant seals and hose materials Page 29 These higher operating temperatures can result in damage to the compressor lubricant and flexible hoses and seals Page 41 With smaller refrigerant charges all the seals joints and
111. oa Arizona California Guam Hawaii Mevada section 609 Enforcement Contact EPA Region IX Mail Code AIR 5 75 Hawthorne Street San Francisco CA 94105 Alaska Idaho Oregon Washington CAA section 609 Enforcement Contact EPA Region X OACQ 107 1200 Sixth Avenue Seattle 98101 54 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE AIR CONDITIONING amp HEATING CUSTOMER QUESTIONNAIRE CUSTOMER Name Phone Date Address City State Zip VEHICLE Year Make Model Color A C System Type 9 Manual O Auto Temp Control Dual Rear Auxiliary Unit PROBLEM SYMPTOM a NoA C No Defrost Poor Cooling Poor Heating Improper Q Air From No Noise Inside Noise Under Fan Blower Wrong Temperature Car Hood Operation Outlet s Control Q Interior Q Engine Q Warning Q Odor Other Water Leak Coolant Leak Light s On See Below WHEN DOES THE PROBLEM OCCUR Always Intermittent When Hot Q When Cold Q At Start Up During Warm At Idle High Engine Driving Away At Road Up Speeds From Stop Speeds Have there been any previous attempts to repair this problem O No O Yes If there were previous repair attempts what was done What parts were installed etc Did previous repairs help the problem O No O Some OA lot O At first but not now Have repairs or service of any kind been recently performed to the vehicle 2 No O Yes If so exactly what was done FURTHER DESCRIPT
112. of the existing refrigerant perform a thorough evacuation and install a known amount If you have a recovery recycling only ma chine consider purchasing an accurate digital scale per haps one with a solenoid type dispensing valve Sometechnicians still attempt to use small cans and pressure gauge readings to charge systems but accurate charging is not possible with this method A O 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE 4 5 mmm eL 1 L i More on Refrigerants and the Proper Use of Refrigerants Whenever you hear the term refrigerant contamination the first thing you probably think of is mixed refrigerants However the most prevalent contaminant particularly in recycled refrigerant is air This section will provide tips on dealing with both of these problems excessive amounts of air in refrigerant and cross contaminated refrigerant Three Questions on Air contaminated Refrigerant 1 What problems are caused by excess air in a vehicle air conditioning system Air in excess of allowable amounts can cause the system to operate at pressures that are higher than normal This can result in noisy system operation and loss of air conditioning performance Air is not a good heat transfer medium as is refrigerant and higher pressures also mean higher condenser temperatures which can also degrade system performance It can also cause the system s high pressure compressor clutc
113. of the refrigerant prior to service is required Equipment Use Since January 1 1992 for CFC 12 and November 15 1995 for HFC 134a and other mobile A C refrigerants any per son employed technician or do it yourselfer servicing the mobile air conditioning pressurized refrigerant circuit for Mobile A C system refrigerants must be recovered with the appropriate re covery machine It is illegal to vent them to the atmosphere F u 4 consideration must comply with the Clean Air Act and must use either refrigerant recovery recycling or recovery only equipment approved by EPA Those working for consider ation receiving monetary value who open the refrigerant circuit must be certified by an EPA approved organization to legally use such equipment to service the system Persons working on their own mobile air conditioning system are not covered under this rule and can add refrig erant without being certified However anyone found to intentionally release refrigerant into the atmosphere un der any circumstance during the repair maintenance or service of mobile air conditioning systems can be fined Fleets of vehicles whether private federal state or local government owned are subject to the regulations be cause the technicians performing the service are paid Oth er examples of establishments covered by the regulations include but are not limited to independent repair shops service stations fleet shops body
114. ollow its manufacturer s instruc tions to assure that proper air purging is taking place Note Refrigerant contamination by air chemical addi tives or other refrigerants can cause system operating problems System Lubricants CFC 12 systems use mineral based lubricants HFC 134a systems use several types of polyalkylene glycol PAG lubricants Different HFC 134a systems require the use of different oils You must in stall the type and viscosity recommended by the system or compressor manufacturer To find out the type you need to use refer to the underhood A Csystem information label or look it up in a service manual or electronic information system To prevent damage to the compressor it is important that the correct type and viscosity of lubricant and correct amount of lubricant is used in an A C system Too little or the wrong viscosity oil can cause internal com pressor failure But too much oil can also cause problems Too much oil can cause the compressor to liquid slug possibly even hydraulically lock up Too much oil can also result in reduced overall system performance The excess oil can heavily coat the interior surfaces of the heat ex changers insulating the refrigerant from those surfaces Do not mix lubricants Use only the type of lubricant speci fied by the system manufacturer The A C system label will identify the vehicle compressor or A C system man ufacturer s recommended lubricant often by
115. on and toxicity of the refrigerant It also identifies refrigerant and lubricant system and material compatibility requirements to be usable in the mobile A C system Published February 1999 SAE J1658 Alternate Refrigerant Consistency Criteria for Use in Mobile Air Conditioning Systems Blend refrigerants consist of a combination of more than one refrigerant This document identifies the proper handling procedure vapor or liquid phase and identifies when the remaining container contents cannot be used due to improper blend consistency Published February 1999 SAE J1659 Vehicle Testing Requirements for Replacement Refrigerants for CFC 12 R12 Mobile Air Conditioning Systems Thisidentifies vehicle tests that must be conducted to establish system performance changes due to the alternate refrigerant Published February 1999 M SAE J1660 Fittings and Labels for Retrofit of CFC 12 R12 Mobile Air Conditioning Systems to HFC 134a R134a This SAE Recommended Practice describes the specific measures required to meet SAE established criteria when retrofitting CFC 12 R12 mobile air conditioning A C systems to HFC 134a R134a with regards to fittings and labeling This document is complete only when combined with the requirements of SAE J1657 SAE J1661 Procedure Retrofitting CFC 12 R12 Mobile Air Conditioning Systems to HFC 134a R134a The purpose of this SAE Recommended Practice is to provide a service procedure for
116. ont CAA section 609 Enforcement Contact EPA Region Mail Code SEA JFK Federal Building One Congress Street Suite 1100 Boston MA 02114 2023 New York New Jersey Puerto Rico Virgin Islands CAA section 609 Enforcement Contact EPA Region Il 2DECA AC 290 Broadway 21st Floor New York NY 10007 1855 Delaware District of Columbia Maryland Pennsylvania Virginia West Virginia CAA section 609 Enforcement Contact EPA Region III Wheeling Operations Office Mail Code 3AP12 303 Methodist Building 11th and Chapline Streets Wheeling WY 26003 Alabama Florida Georgia Kentucky Mississippi North Carolina South Carolina Tennessee CAA section 609 Enforcement Contact EPA Region Atlanta Federal Center 61 Forsyth Street SW Atlanta GA 30303 Illinois Indiana Michigan Minnesota Ohio Wisconsin CAA section 608 Enforcement Contact EPA Region V AE17J 77 West Jackson Blvd Chicago IL 60604 3507 Arkansas Louisiana New Mexico Oklahoma Texas CAA section 609 Enforcement Contact EPA Region VI BEN AA 1445 Ross Avenue Suite 1200 Dallas Texas 75202 lowa Kansas Missouri Nebraska CAA section 609 Enforcement Contact EPA Region VII Mail Code APCO ARTD 901 North 5th Street Kansas City KS 66101 Colorado Montana North Dakota South Dakota Utah Wyoming section 609 Enforcement Contact Region VIII Mail Code 8ENF T 999 18th Street Suite 500 Denver CO 80202 2466 American Sam
117. other causes that shortage was fueled by increased demand for motor vehicles in developing nations More new cars are rolling off assembly lines in these countries and as the demand for HFC 134a increased stocks dwindled A casual buyer would believe the label but this tank contained R415B a blend refrigerant not approved for use in vehicles As worldwide supplies shrank some suppliers resorted to creative and not so creative ways to meet the demand for HFC 134a In the process they violated U S customs trademark and environmental laws More recently HFC 134a that does not meet the chemi cal requirements for purity has been sold in world mar kets Now industry purity specifications SAE J2776 and ARI 700 2006 can be identified on packaging and con tainers of refrigerant which meets the requirements As with everything else the Latin phrase caveat emp tor buyer beware applies Be on the look out for coun terfeit HFC 134a cylinders at a distributor near you and always examine the packaging carefully You can report incidents of suspected fraud to the EPA s toll free hotline at 1 800 296 1996 the two refrigerants The raising of system operating pres sures above normal can result in poor A C performance and could also cause damage to system components Also on a recovery recycling machine so equipped mixed cross contaminated refrigerant inside the machine s tank could reach a pressure high enough to fool
118. ou can see it glow under a UV lamp 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE CERTIFICATION TRAINING MANUAL Like this technician always be sure to wear the special goggles that came With your UV dye leak detection kit Not only do they protect your eyes from the UV light they also make dye traces at leak sites stand out better Looking for Leaks When scanning the system with your lamp put on the supplied glasses and examine all fittings lines and compo nents A helpful trick is to use a mirror to reflect the UV light underneath the components If you don t have space for a mirror then use a clean rag to wipe underneath the com ponent and hold the rag under your lamp You can use a mirror to reflect the UV light underneath components in hard to see locations If dye is present at a leak site you should see it glowing EE M5 How much time should it take for the leak to appear Dye makers say that the dye could take anywhere from five minutes to five days to show up at the leak site s so don t expect the dye to show up immediately every single time The length of time depends on the size of the leak In cases where a leak does not become readily apparent you might want to consider installing the dye instructing the customer to drive the car and use the A C for a week or so then bring it back so you can look for visual evidence of leakage Do not let the customer run the car for months befo
119. oved from a system using dedicated recovery only equipment and properly disposed of There are currently two types of equipment that can be used to recover contaminated refrigerant Recovery only units offered by some equipment manufacturers that are specifically designed for this purpose You may dedicate a CFC 12 or HFC 134a recovery unit specifically for the purpose of recovering contaminat ed refrigerant Caution If the refrigerant contains flammable substances such as propane and butane a fire or explosion could occur if the refrigerant is exposed to an ignition source within the NM 3 equipment Recovery equipment that has been certified for use with CFC 12 or HFC 134a is not approved for use with a flammable refrigerant and may become a safety hazard if used Make sure you determine if features have been in corporated into your equipment to guard against these hazards Also refrigerant containing flammable substances may be considered hazardous and you must follow any local state or federal requirements governing the storage and disposal of ignitable materials visit www ecarcenter org ecartour html for more information on specific disposal re quirements Contaminated refrigerant must be sent off site to an EPA certified refrigerant reclaimer for either reclamation or de struction A list of EPA certified refrigerant reclaimers can be found on the web site at www epa gov ozone ti tle6 608 reclamation rec
120. ow for sure is to connect a refrigerant identifier to the system and take a reading 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE When the Label Lies Many shop owners and technicians may remember the previously prevalent black market in CFC 12 But as CFC 12 s use has waned a new black market has emerged this time in HFC 134a Cases of counterfeit HFC 134a are not exactly new Sever al years ago a Harp refrigerant cylinder and its box were labeled as containing HFC 134a when in fact the refrig erant in the cylinder was CFC 12 A close examination of the box reveals the fraud Harp manufactures its cylin ders and boxes in the United Kingdom yet the emblem on the box indicates it was manufactured in Portugal E AJ HARP134a 124 mm Um oom undc ms humo akedi nS nn msc uem r Hm MONET e 1146 i The box says Portugal but only the most knowledgeable purchaser would know that legitimate Harp products are packaged in the UK The tank in side this box was filled with CFC12 At the time the price for CFC 12 in Malaysia where the cylinder was discovered was much lower than that for HFC 134a Profit margin appears to have been the main motive for the alleged fraud in this case 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE During 2005 HFC 134a was in short supply Among
121. perat ing pressures which can also cause poor cooling perfor mance and even component damage Page 29 Lubricant circulation in the system relies upon a proper refrigerant charge and inadequate refrigerant and therefore lubricant flow in the refrigerant circuit will result in increased compressor operating temperature These higher operating temperatures can result in damage to the compressor lubricant and flexible hoses and seals 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Condenser As with the compressor the fix for a leaking or failed con denser is usually to replace it and following are some im portant considerations that the technician should keep in mind Page 26 Today s condensers have very tiny refrigerant multi flow passages This is why attempts to flush debris clogged condensers are often not successful Note The decision to flush or not to flush A C systems or components is an important repair issue Page 31 Also some replacement condensers require a change in system charge spec usually a reduction Evaporator The real challenge is finding leaks in the evaporator due to its location If the evaporator is found to be leaking it should be replaced with a new evaporator The technology of current automotive evaporators is such that repair is not a viable option Evaporator replacement involves signifi cant labor making a repeat failure particularly undesirable For more information r
122. rant recovery or recovery recycling equipment must maintain re cords of the name and address of any facility to which refrigerant is sent Any person who sells Class substances chlo rofluorocarbons CFCs or Class Il substances hydrochlorofluorocarbons HCFCs for use as mobile A C system refrigerants must prominently display a sign which states It is a violation of federal law to sell containers of Class and Class Il refrigerant to any per 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE MS son whois not properly trained and certified to operate approved refrigerant recovery recycling equipment Section 608 of the Clean Air Act requires that all per sons who sell CFC and HCFC refrigerants must retain invoices that list the name of the purchaser the date of the sale and the quantity of refrigerant purchased However since the sale of small containers of CFC 12 is restricted to technicians certified under Section 609 these record keeping requirements do not apply to the sale of small containers of CFC 12 Mobile A C service facilities must allow an authorized representative of the EPA entry onto their premises upon presentation of appropriate credentials and give the authorized representative access to all re quired records Further Mobile A C Service Rules and Regulations Every compensated technician that opens the refriger ant circuit must be certified This includes technicians that only add refrigerant to
123. re coming back for their visual inspection and expect to see dye traces Some of these dyes will wash off or lose their fluorescence over time Also keep in mind that with some customers if you just put in dye and tell them to come back you can almost bet they won t until the system stops cooling And by then the compressor may have taken a beating due to a lack of lubri cation from reduced refrigerant flow After all system leaks have been identified and the neces sary repairs completed the system should again be thor oughly leak tested You should find that using an electronic detector along with ultraviolet dye will often lead to great leak detection results Flushing A C Systems Most A C system manufacturers recommend that flushing not be performed Open vent flushing often will not re move debris from a system Connecting flush equipment to the system service ports even with the valve cores re moved will not provide adequate system flushing and may not result in the removal of debris and other substances Many A C system manufacturers consider the use of in line filters to be an effective method of trapping debris In liquid line filters can be installed to trap debris that may be in an A C sys tem after it has suffered a catastrophic compressor failure Filters of this type are available from a number of different A C parts suppliers Many A C system and component manufacturers also have reservations concerning
124. s tems to HFC 134a Air conditioning system manufacturers procedures follow these SAE guidelines Conversion of a CFC 12 system not following these procedures could result in operational problems Only CFC 12 and HFC 134a recovery recycling and charg ing equipment are currently covered by SAE standards When and if OEM approved alternate refrigerants enter the market SAE standards related to those refrigerants will be issued CFC 12 and HFC 134a are the only refrigerants approved by vehicle and A C system manufacturers Use of alternate re frigerants which are not approved could result in damage to A C system components Servicing mobile A C systems with alternate refrigerants could also contribute to the con tamination of CFC 12 and HFC 134a recycled refrigerant supplies All mobile A C system manufacturers encourage the continued use of CFC 12 in systems originally designed to use it If and when CFC 12 is no longer available most CFC 12 systems can be retrofitted to operate with an alter nate refrigerant As determined by the vehicle or system manufacturer ad ditional retrofit requirements and recommendations may include the installation of new o rings and or seals new desiccant a different lubricant replacement of refrigerant controls increased condenser capacity and other modifi cations Not following OEM recommendation may result in system damage loss of performance and could also affect component warranties
125. s accumula tors located in the low pressure side of the system hold more refrigerant and oil than do receiver driers During the recovery process as the system is drawn into a vacuum and pressure in the accumulator is lowered the accumulator becomes very cold with external frost some times visible on the accumulator This makes it even more difficult to extract remaining refrigerant from it If liquid refrigerant has not been removed and the refrigerant lines are opened as the accumulator warms a sudden release of refrigerant and oil can occur Heating the accumulator with devices such as a hair dryer or electric heating pad will raise the pressure in the accu mulator and reduce the amount of time necessary for re frigerant removal When recovering refrigerant from any mobile A C system continue the recovery process until the system has been reduced from a pressure to a vacuum At this point pause operation of the recovery machine for five minutes and check A C system pressure If pressure has risen above vac uum additional recovery is required to remove remaining refrigerant Repeat the recovery process until the vacuum remains stable without rising for two minutes Heating an accumulator during refrigerant recovery is a good idea The heat Will raise pressure inside the accumulator allowing it to more easily outgas refrigerant it contains This will reduce the amount of time necessary for more complete refrigerant r
126. s a perfluorocarbon which has extremely high global warming potential and lifetime USE CONDITIONS Many refrigerants including R401A made by DuPont R401B DuPont R409A Elf Atochem Care 30 Calor Gas Adak 29 Adak 12 TACIP Int l MT 31 Millennia Tech and ES 12R Intervest have not been submitted for review in motor vehicle air conditioning and it is therefore illegal to use these refrigerants in such systems as an alternative to CFC12 Acceptable Subject to Use Conditions regarding fittings labeling no drop in and compressor shutoff switches Unacceptable illegal for use as 12 substitute in motor vehicle air conditioners 3 Although some blends contain flammable components all blends that are Acceptable Subject to Use Conditions are nonflammable as blended 4 Freezone contains 2 of a lubricant HCFC22 content results in an additional use condition must be used with barrier hoses 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE No Ua E Table 6 MVAC Refrigerants Fitting Sizes These fittings and labels must be used with alternative refrigerants when used in motor vehicle air conditioning systems For more details see EPA s fact sheet titled Choosing and Using Alternative Refrigerants for Motor Vehicle Air Conditioning available from the hotline and on the website The list includes all refrigerants found acceptable subject to use conditions in motor vehicle air conditioning as o
127. s having a refrigerant other than HFC 134a will have to be serviced in the United States HFC 134a has been considered as a global refrigerant and with the requirement for its phase out in Europe the in dustry is striving to identify a replacement refrigerant that can be used in a new environmentally friendly global mo bile air conditioning system Several possible approaches including unique air conditioning system designs and new refrigerants are being considered R744 Carbon Dioxide Systems To meet the European low GWP refrigerant requirements vehicle manufacturers have developed mobile air condition ing systems that use carbon dioxide R744 as a refrigerant R744 has the lowest GWP value of new refrigerants being considered Carbon dioxide systems will require different types of components compared to HFC 134a systems R744 systems operate at pressures 5 to 10 times higher than to HFC 134a and HFC 152a systems The chart below compares the container pressure for HFC 134a R744 and Fr saues al 12103 MOT 43 1327 ET 7 224 MFLD 1323 11 450 427 Ti HFC 152a at 70 F 21 C These pressures will go higher as the containers become warmer Carbon dioxide is hazardous and therefore also requires system design features to address safety for vehicle oc cupants and service personnel In addition new service equipment and service procedures as well as specific train ing and possible certi
128. se a reflector and lens to direct and filter the light properly The UV lamp should also be UL listed The coloration of the special yellow glasses that come with most UV dye leak detection systems enhance the dye s flu orescence and also protect your eyes from UV rays UV rays are harmful to your eyes and you should not stare at a UV lamp just as you would not stare directly at the sun Before You Begin Using UV Dye to Find Leaks Always start with the dye manufacturer s instructions They vary slightly but the process is pretty straightforward If you are working on a newer vehicle say five years old or newer first check to see if there is factory installed dye in the A C system To prevent damage leak dye should not be added to a system unless the vehicle manufacturer has approved the specific product Choosing Your Delivery System A MACS survey found that techs did not have a consensus on the best way to install dye into A C systems It seems that techs are using just about every method from in hose dye canisters to caulking gun type syringe type injectors to simply pouring dye into an open system No matter which delivery system you choose before install ing your dye make sure you have a full refrigerant charge to allow the dye to thoroughly circulate in the system Add the dye let it circulate Refrigerant escapes at the leak point as gas but the dye is brought to the leak site with the lubricant remaining behind so y
129. se the MACS Customer Questionnaire which can be found in the back of this manual You may photocopy it for your use Always try to find out as much as you pos sibly can about any vehicle on which you intend to perform A C service and also about any refrigerant that you intend to purchase To be as safe as possible you should use a re frigerant identifier on every system you re going to work on and on every tank of refrigerant that you intend to buy see the next page for When the Label Lies Mixed cross contaminated refrigerant is harmful for a number of different reasons If you mistakenly draw mixed refrigerant into your service equipment not only could it possibly damage the equip ment but unless detected you will contaminate every other vehicle that you use the equipment to service Even a small amount of one refrigerant mixed with another can ruin the entire batch Mixed refrigerants can result in elevated system operating pressures and this includes CFC 12 mixed with HFC 134a A mixture of these two refrigerants will raise operating pressures to a point higher than either would ever reach by itself in a normally operating system and how high the pressure goes is determined by the mixture ratio between Even though CFC 12 system may be equipped with a retrofit label and conversion fittings that doesn t in any way provide proof of the type of refrigerant that may be in the system or its purity The only way to kn
130. seases Plant and Marine Effects Crops and other ecosystems can also be adversely affect ed by increased exposure to UV radiation In greenhouse studies approximately two thirds of the crops exposed to elevated levels of UV radiation proved sensitive Certain marine organisms may also be sensitiveto increased exposure to UV radiation Although it is difficult to design experiments replicating aquatic environments research suggests that increased exposure to UV radiation can have adverse effects on productivity and species diversity Other Impacts Ground level Ozone Stratospheric ozone depletion in creases the rate of formation of ground level ozone a ma jor component of smog Stratospheric ozone depletion can increase the rate of formation of ground level ozone which is a major component of smog Degradation of Polymers Ozone depletion accelerates weathering i e chalking yellowing and cracking of plas tics used in outdoor applications Climate Change CFCs and HFCs as well are greenhouse gases which contribute to global warming and rising sea levels Global Problem Ozone protection is a global concern CFCs and halons have been produced in the United States and in other de veloped countries and are being used in nations around the world Given their long atmospheric lifetimes they have become widely dispersed over time As a result the release of these chemicals by one country can migrate up CERTI
131. speed to implement refrigerant containment and recycling of refrigerants in automotive air conditioning systems and to develop systems that use a non ozone depleting refrigerant HFC 134a Now it s all up to you If you fail to operate and maintain your refrigerant recovery recycling service equipment as required by federal law and as recommended by the equipment manufacturer the development of recycling technology to reduce the release of refriger ant to the atmosphere will have been in vain You are key to the success of the national refrigerant recovery recycling program and a lot is riding on the success of the tech nology Please take the time to read this manual completely and do your part to make the recovery recycling program work Note on Refrigerant Terminology This manual makes repeated reference to two refrigerants CFC 12 and HFC 134a CFC 12 also known as R12 is a chlorofluorocarbon and is composed of the elements chlorine fluorine and carbon Its actual nomenclature is dichlorodifluoromethane HFC 134a also known as R134a is a hydrofluorocarbon and is composed of the elements hydrogen fluorine and car bon Its actual nomenclature is 1 1 1 2 tetrafluoroethane 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE 5 IT Refrigerant Recycling and Service Procedures for Mobile Air Conditioning Technicians 1 niger T 1 ENVITONHION eee
132. t of vehicle air conditioning systems This standard provides testing and acceptance criteria for determining the stability and compatibility of additives and flushing materials solutions with A C system materials and components that may be intended for use in servicing or operation of vehicle air conditioning systems This standard does not provide test criteria for additive compressor lubricant or flushing solution effectiveness such testing is the responsibility of the additive and or solution manufacturer supplier It is not the intent of this document to identify the requirements for Standard J2297 Ultraviolet Leak Detection Stability and Compatibility Criteria of Fluorescent Refrigerant Leak Detection Dyes for Mobile R134a Air conditioning Systems All leak detection materials must meet the requirements of J2297 Published in 2005 SAE J2776 Refrigerant Purity and Container Requirements for New HFC 134a 1 1 1 2 Tetrafluoroethane Refrigerant Used in Mobile Air Conditioning Systems The purpose of this SAE Standard is to establish the minimum level of purity required and container specifications for new HFC 134a refrigerant used in mobile air conditioning A C systems The refrigerant shall meet all the requirements as identified in ARI 700 2004 and all future ARI standards for HFC 134a Published October 2006 Technician Service Procedures SAE J1628 Technician Procedure for Using Electronic Refrigerant Leak Detectors for Service
133. that will attach to the automotive service equipment Refrigerant containers not having this fitting may not meet the SAE J2776 purity requirements 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE CERTIFICATION TRAINING MANUAL Recovering Refrigerant from Disposable Cylinders Before they are discarded disposable refrigerant cylinders should be connected to recovery equipment and brought to a vacuum This will ensure that all refrigerant has been removed The cylinder should then be marked Empty Note Some disposal facilities will not accept these cylin ders unless some type of visual assurance exists that the cylinder is completely empty such as a hole drilled in the cylinder Von flammable Liquefied 1 4 1 2 CAS No amp 1 1 97 5 Tiz Automotive alye Make sure new HFC134a you intend to purchase meets the SAE J2776 and or the ARI 700 2006 purity standard s and has a 1 2 inch Acme tank fitting Notes Before they are discarded disposable refrigerant cylinders should be con nected to recovery equipment and brought to a vacuum This will ensure that all refrigerant has been removed Empty refrigerant cylinders should be marked Empty before disposal A 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Field Coupling of Flexible Hose Assemblies SAE J2064 is an engineering standard for joint integrity of hose couplings This standard is important because it co
134. the fitting itself should not be deformed Oblong out of round or irregular crimps usually indicate worn die carriers or a mismatch of the two dies If the correct hose is used with the correct fittings and the assembly operation is performed properly you should be able to build and repair hose assembles that meet the re quirements for reduced leakage Replacement Refrigerants and Retrofitting Mobile A C Systems Retrofitting CFC 12 systems to use an alternate refrigerant is permitted provided that correct procedures are followed EPA regulations require that CFC 12 systems undergoing retrofit must have ALL of the CFC 12 recovered appropri ate conversion fittings must be installed on all of the origi nal CFC 12 service ports a new A C system information label must be affixed to the vehicle and a high pressure compressor cut off switch must be installed IF the system does not already have one AND it contains a high pressure refrigerant relief device In addition depending on the re frigerant being used the installation of barrier hoses on systems that do not already have them may be required The SAE at the request of the EPA and the mobile A C industry developed retrofit guidelines Conversion of a CFC 12 system to use HFC 134a is covered by SAE standards J1660 Fittings and Labels for Retrofit of CFC 12 Mobile Air Conditioning Systems to HFC 134a and SAE J1661 Proce dure for Retrofitting CFC 12 Mobile Air Conditioning Sy
135. the machine into activating its automatic air purge feature This would cause refrigerant to be released the atmosphere Mixed refrigerants cannot be separated by recycling ma chines and are considered hazardous waste They must be transported to an off site facility for reclamation or de struction Two More Issues Concerning Refrigerant and System Contamination Just because a vehicle is equipped with a retrofit label and conversion fittings it would not be wise to assume that the refrigerant in the system is a match to the fittings and the information on the label There have also been cases of CFC 12 systems being directly charged with HFC 134a with no labels fittings or any other type of indication that this was done A vehicle could have passed through any num ber of hands before entering your shop and there s no tell ing what could have happened along the way Also keep in mind that even approved chemicals such as dye or lubricant can become contaminants if they are in a system in excessive amounts This also applies to approved OEM vehicle system manufacturers flushing material that may not be completely removed from a system at the con clusion of a flushing procedure Recovery and Disposal of Contaminated Refrigerant Under federal law contaminated refrigerant cannot be vented Recovery recycling equipment is not designed to recycle or separate contaminated refrigerants Contami nated or unknown refrigerant must be rem
136. the use of solvents to flush systems Other than possible ineffectiveness the manufac turers main area of concern is the fact that some solvent may remain in the system because depending upon a sol 26 CERTIFICATION TRAINING MANUAL vent s boiling point a vacuum pump may not remove all of it even after a prolonged deep vacuum This residual sol vent can dilute the lubricant which can lead to inadequate compressor lubrication and possible subsequent compres sor failure It could also possibly affect the chemical stabil ity of the refrigerant seals and hose materials w 7 _ t LE m E E E i Today s condensers have very tiny refrigerant multi flow passages Not only can t you even fully insert a toothpick into some of them others are so small a push pin will barely go in This is why attempts to flush debris clogged con densers are often not successful Flushing compounds that are certified to SAE standard J2670 Stability and Compatibility Criteria for Additives and Flush ing Materials Intended for Use in Vehicle Air conditioning Systems Using HFC 134a have been tested for compatibility with A C system components and found to be compatible However this does not assure they will clean the component being flushed for more information on J2670 and other SAE standards that apply to mobile A C system service refer to the appendix on page 48 2008 MOBILE AIR CONDITIONING SOCIET
137. this activity is illegal In other rulings the EPA prohibits the venting of other refrigerants including HFC 134a and blend refrigerants containing HCFCs used in mobile air conditioning systems To protect the ozone layer the United States and over 180 other nations ratified the 1987 Montreal Protocol on Sub THE ENVIRONMENTAL ISSUES Ozone is a pungent slightly blue gas that absorbs certain wavelengths of the sun s radiation Ozone is concentrated in a part of the atmosphere called the stratosphere The stratosphere is located between 10 and 30 miles above the earth s surface Stratospheric ozone should not be confused with ground level ozone which is commonly re ferred to as smog The ozone layer acts as a shield against harmful solar Ultra violet Beta UVB radiation Ozone normally absorbs UVB Decreasing the amount of stratospheric ozone results in higher levels of UVB reaching the earth s surface and this increase can be harmful to humans animals plants and the environment as a whole It is estimated that for every percentage point that stratospheric ozone is reduced ex posure to ultraviolet radiation is increased by 1 5 to 296 Substances like chlorine from synthetic chemicals called chlorofluorocarbons CFCs and bromine from chemicals called halons when released to the atmosphere react in a way which reduces the amount of ozone in the strato CFCs were used for many different purposes including refrigerants in
138. this idea that a little more refrig erant should be helpful So they add refrigerant If they re unlucky along with something else they do or a part they replace the system cools better in the shop than when it came in Why is that unlucky Because when it s really hot and the car is slow moving in traffic the high side pres sure goes way up and the system shuts down Then maybe some other shop gets the job does an evacuation and re charge and enjoys a phantom repair at the expense of the first shop s reputation Charging Systems with Small Cans or by Attempting to Use Pressure Readings Part of this one s already been mentioned but If you re charging with small cans or even using 30 pound cylinders but trying to charge a system going by gauge readings or using any other method that does not involve accurately weighing the amount of refrigerant entering the system STOP Pressure gauges are a diagnostic tool but you can t use them to meter refrigerant into a system and no vehicle or system manufacturer provides exact pressure specs for a precise charge Even if you have reliable pressure readings as we ve already pointed out there isn t enough of a pres sure difference to indicate over or undercharge System pressure readings whether the system is operat ing or off will not identify the amount of refrigerant in a system The only way to assure that any given system s re frigerant charge is correct is to recover all
139. titutes for CFC 12 Reviewed Under 5 SNAP Program as of March 29 2006 Acceptable Subject to Use Conditions Name Name 1 Manufacturer Components HCFC HCFC HCFC HFC Isobutane 22 124 142b 134a R 600a Intercool FRIGC 6 13 95 Distribution FR 12 800 555 1442 Free xa Hi Tech RB 276 4 5 22 96 Refrigerants LLC 800 530 4805 Ikon 12 5 22 06 Ikon Corp Composition claimed as confidential business information 601 868 0755 PU 10 16 96 People s Welding GHG vt 10 16 96 People s Welding 800 382 9006 People s Welding GHG HP 800 382 9006 Autofrost 10 16 96 McMullen Oil Chill It 5 Products 800 669 5730 Hot o 10 16 96 ICOR Kar Kool 5 800 357 4062 Technical Freeze 12 10 16 96 Chemical 800 527 0885 GHG X5 6 3 97 People s Welding 800 382 9006 SP34E 12 18 00 Solpower Composition claimed as confidential business information 888 289 8866 RS 24 12 20 02 Refrigerant Composition claimed as confidential business information Products Ltd wm 9 Unacceptable Substitutes Date Manufacturer Reason Flammable blend of hydrocarbons insufficient data to demonstrate safety Contain CFC 12 which is inappropriate in a CFC 12 substitute Flammable blend of hydrocarbons insufficient data to demonstrate safety Duracool 12a 6 13 95 Duracool This blend is identical to HC12a in composition but is manufactured by a different company Limited R405A 6 13 95 Greencool Contain
140. to replace it rarely are compressors repaired the manual includes important cautions and relevant information re lated to compressor replacement such as Page 18 To prevent damage to the compressor it is im portant that the correct type and viscosity of lubricant and correct amount of lubricant is used in an A C system Page 22 With this limited amount of refrigerant you can determine if the system has a leak but you cannot deter mine if the system will provide cooling If you intend to op erate the compressor the system must contain its specified amount of refrigerant Page 23 Loss of refrigerant can reduce oil circulation even before the low pressure switch or other sensor shuts down power to the compressor clutch It is important to determine if there were multiple leak sources Another leaking system part and loss of refrigerant could have caused the compressor failure Page 25 It is important that dyes be safely and properly used Excessive dye can result in compressor damage Page 26 In liquid line filters can be installed to trap de bris that may be in an A C system after it has suffered a catastrophic compressor failure Page 28 The only way to remove significant moisture from a system is to replace the receiver drier or accumula tor Page 28 Undercharges can result in poor cooling and even worse poor lubricant circulation which can lead to compressor failures Overcharges can result in high o
141. un capped and open to the atmosphere for an extend ed period of time moisture can enter the system and result in the desiccant becoming saturated It is advisable to keep the refrigerant circuit connections closed If left open for a period longer than normal servicing activity the desiccant should be replaced to provide moisture control Systems left unsealed during vehicle collision repairs can result in moisture entry Properly Charging and Recharging Mobile A C Systems To reduce refrigerant emissions newer mobile A C systems use less refrigerant Because of this today s newest systems are critical charge A critical charge system is one that is substantially less tolerant to variations in charge Undercharges can result in poor cooling and even worse poor lubricant circulation which can lead to compressor failures Overcharges can result in high operating pressures which can also cause poor cooling performance and even component damage During hot weather conditions over charged systems can experience system shutdown from the high side pressure control switch due to high system pres sure Because of this mobile A C systems should only be charged with known amounts by weight of refrigerant The customary top off method is no longer acceptable Compounding the problem is that some charge equipment considered good a few years ago cannot provide the accu racy you need for late model systems For example BMW an
142. v ers the HFC 134a refrigerant hoses you install or repair Im properly coupled hose assemblies are a reliability problem and result in loss of refrigerant With smaller refrigerant charges all the seals joints and fittings have to be de signed to leak far less When CFC 12 systems had larger charges leakage of a pound in a year was considered tolerable What was once normal seepage isn t normal anymore and motorists now object to both the need for frequent service and the environmental risks In the early to mid 1990s high leakage rates were not sur prising but not anymore In today s small capacity systems just a few ounces lost is enough to affect performance And now the systems are getting even tighter A MACS survey showed that half of the replacement cou pled hose assemblies are field coupled instead of installing new replacement assemblies And because some of those shops make up hose assemblies for other shops they have a multiplier effect The following are some suggestions that will probably help you do a better job Assembly crimped rotated and recrimped CERTIFICATION TRAINING MANUAL Practical Matters Typical problems with the field coupled hoses are damage to the coupling and incorrect crimping To assure the best field coupled hose and minimize refrig erant leakage follow the hose coupling procedures for tube and hose fit and coupling requirements as outlined by the supplier Make
143. vaporator OT System 50 F Shop Area Temperature Recovery Times Pre heating Recovery Equipment Shut off Setting 10 hg Vacuum pun o gt o c o o c o c o D pus c E o gt o c o o Recovery 1st 2ndrcvry 3rdrevry rcvry Recovery 1st 2nd revry 50 F Recovery 24 hr 48 hr 72 hr 50 F Recovery 24 hr Heating Chart A 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE Refrigerant Recovery Single Evaporator OT System 70 F Shop Area Temperature Time Lapse Pre heating g gt c o D c p o c E g n gt o c o o Recovery 1st 2nd revry 3rd revry Ath rcvry Recovery 1st 2nd rcvry 70 F Recovery 24 hr 48 hr 72 hr 70 F Recovery 24 hr Heating Chart B Any refrigerant not removed from a system during recovery remains in it and could cause potential problems If you don t physically apply heat to the system components especially accumulators before you start a recovery process you should first run the engine up to operating temperature so at least some heat will transfer to the A C components What happens to the refrigerant you didn t get out of the system during recovery If the system is opened the remaining refrigerant will be vented to the atmosphere and you have discarded perfect ly good reusable refrigerant If your vacuum
144. w re frigerants SAE I MAC Program In 2004 the industry established the industry and govern ment sponsored SAE Improved Mobile Air Conditioning I MAC Cooperative Research Program to reduce system energy requirements as well as reduce refrigerant emis sions from HFC 134a mobile air conditioning systems 2008 MOBILE AIR CONDITIONING SOCIETY WORLDWIDE The goals of the project were to identify technologies that will Reduce direct system refrigerant leakage by 5096 Improve system efficiency by 3096 Reduce system loads by 3096 Reduce the impact of service refrigerant losses by 50 The service sector contributes to the release of refrigerant Using professional service procedures and equipment will reduce the release of HFC 134a The I MAC goal is reducing refrigerant loss by 5096 through the use of better equip ment and improved procedures Improved HFC 134a Systems Improved HFC 134a systems are more efficient use less refrigerant charge and have less refrigerant loss over their lifetime The SAE I MAC Cooperative Research program accom plished its goals and many of these technologies have been introduced into HFC 134a mobile air conditioning systems and service equipment As new technologies are developed expect to see further changes in mobile A C systems Notes Metal Gasket Barrier Hose Cover Elastomer Layers Textile Braid Polyamide Layer Reduced Refrigerant Loss Systems The use o
145. which can produce readings similar to those in the charts on page 36 mimicking air contamination In other words the pressure temperature method cannot identify whether the higher readings are being caused by air in the refrigerant or if they are being caused due to refriger ant cross contamination Pressure Temperature MethodforDetermining theAmount of Air Contained Within Refrigerant in a Container To determine if a tank of recycled refrigerant contains an excessive amount of air the tank must be stored at a temper ature of at least 65 F for a period of 12 hours protected from direct sunlight It is also advisable not to store tanks directly on the cement shop floor since the floor temperature can af fect the tank temperature Placing some form of insulation such as a piece of wood between the tank and the floor will help stabilize the tank pressure If these conditions have been met a check for air may be performed as follows Install a calibrated pressure gauge to the refrigerant con tainer The gauge should be graduated in 1 psi divisions TANK This is a typical tank pressure gauge on a recovery recycling machine Its reading with the ambient temperature reading and Tables 3 and 4 on page 36 can be used to determine if excess air is in the refrigerant storage tank If the pressure reading is too high air must be purged from the tank until the gauge reading matches the proper one listed in the table Still a refrigera
146. with failed compressors The chemical analysis of the refrigerant removed from these vehicles showed very little contamination However the data did identify moisture refrigerant oil and non con densable gases air as contaminants in used refrigerant which could affect system performance and life From the field study results the task force established specifications for recycled refrigerant and in December 1988 asked the world s auto manufacturers to help deter mine and approve a level of purity for recycled refrigerant The level of purity was established SAE developed recovery and recycling standards for equip ment to meet refrigerant purity requirements for on site processing and direct reuse in mobile A C systems Subse quently vehicle and A C system manufacturers accepted recycled CFC 12 and HFC 134a as meeting the appropriate SAE standard for service and warranty repairs p am We en En GO us zi d MN 5 i us a While the actual recycling process may vary between ma chines and manufacturers the manufacturers must certify the machines to the requirement for each refrigerant and affix a label to the machine stating that it meets the stan dard of purity The Switch to HFC 134a Refrigerant Starting with some 1992 models with completion by the 1995 model year HFC 134a replaced CFC 12 Changes in systems designs were required to assure that HFC 134a sys tems performed equa

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