TESTING 2011 A/C SERVICE REPORT

Transcription

1 TESTING BY PAUL WEISSLER The a/c scene has been pretty fuzzy for the last few years, ever since it became obvious that a new refrigerant was on the horizon. The picture s begun to come into better focus, and we ll explain why. Photoillustration: Harold A. Perry; images: Thinkstock 24 April 2011

2 1234yf... After participating in a recent meeting of the SAE Interior Climate Control Committee and attending the annual Mobile Air Conditioning Society (MACS) convention in Orlando, we have several developments to report. First off, we re sure that car manufacturers will start installing R-1234yf in new cars starting sometime late this year in Europe and probably next year in the U.S. And we have a General Motors announcement that it will install this refrigerant in all of its car lines in the 2013 model year, which officially begins on Jan. 1. But we also foresee a number of problems with a changeover from R-134a, and we mean more than the issue of very mild flammability that R- 1234yf, the low-global-warming-potential (GWP) alternative refrigerant, first brings to mind. As we said last year, the deep wholesale cost figures to be about $45/lb., which is about nine to ten times the present cost of R-134a. (R- 1234yf likely would be somewhat less expensive perhaps up to 10% or so for a Photos: Credit April

3 vehicle manufacturer who negotiates a multiyear supply contract.) The only place where R-1234yf is currently legally required is in the European Community, where a phase-out of R-134a in new type vehicles had to begin this past January. Retail price to the motorist there could be $100/lb. Well, which cars have changed over in Europe? Not one so far. The manufacturers juggled their introduction schedules so that they don t face the issue until very late this year, because there are no production quantities of R-1234yf available anywhere at any price. The first production is due sometime later this year, when the first large-scale production plant comes on line in China. The plant is a joint venture of Honeywell and DuPont, and there is no competitive effort underway, a problem that can be traced to a series of recently obtained patents held by Honeywell and failure to negotiate licensing agreements with other leading manufacturers. Most of them have filed a lawsuit in Europe to overturn these patents, which they consider weak because of prior patents and the time that has passed since the refrigerant s discovery over 40 years ago. Why are U.S. vehicle manufacturers, who aren t under a legal mandate to introduce R-1234yf, planning to do so? As EPA engineer Brian Nelson explained, there s a special credit of grams per mile of carbon dioxide that can be applied against a schedule to reach a carbon dioxide emissions level of 250 grams/mile. And that translates into a Corporate Average Fuel Economy (CAFE) figure of 35.5 mpg. We won t go into the mathematical details of the federal program, but accept the fact that carmakers can earn a significant credit toward meeting those fuel economy numbers if they use a low-gwp refrigerant and right now, R-1234yf is the only viable game in town. Total cost for the refrigerant credit, including refrigerant and one new and one upgraded heat exchanger, is reportedly under $100 per The two main refrigerants you ll be working with for the foreseeable future are stored in their own jugs R-134a in the light blue jug at left, R-1234yf in the white tank with the red band at right. car on average. For a company that absolutely needs those credits to meet the regulatory requirement, it could be considered a bargain. R-1234yf is conceded by industry experts to be very expensive to make. Even if every refrigerant maker were producing it, competition might not drive the price down very far, certainly to nowhere near the current price of R- 134a. It would take the imposition of a huge tax on R-134a to get it close to the price of R-1234yf. Perhaps some environmentalists would like to see this, but tax increases To Evaporator High-Temperature, High-Pressure Liquid Refrigerant Low-Temperature, Low-Pressure Gaseous Refrigerant Outer Tube Inner Tube To Cooler Compressor are not popular these days. Remember that although the California Air Resources Board (CARB) was able to get the small refrigerant can industry to produce a returnable R-134a can with a refundable deposit, completing the agreement was a struggle even in a state with an environmental ethos. And although CARB has proposed a ban on R-1234yf in small do-it-yourself cans because of its flammability, it s in another legal fight with the small can makers on that. The EPA has a ban on any DIY sales under consideration, but hasn t moved that train onto a track. Furthermore, R-1234yf is not as efficient as R-134a, so to provide equivalent performance, the carmakers all will be installing internal heat exchangers (IHXs) units that transfer heat from liquid refrigerant in the high-pressure line to the cooler refrigerant gas in the low-pressure (suction) line to the compressor. This is a known way to enhance performance and efficiency of the liquid refrigerant in a system designed for it. The IHX is already used in some R-134a systems, such as on the 2011 Toyota Sienna, where it also earns one of the EPA credits for a/c efficiency upgrades. However, this additional heat exchanger, EVAPORATOR COOLER COMPRESSOR ENGINE COOLER CONDENSER This tube-within-a-tube internal heat exchanger, called a subcool accelerator by Toyota, is used to increase efficiency. It s needed on R-1234yf mobile air conditioning systems to match R-134a cooling performance. Photos: Paul Weissler 26 April 2011

4 which is one of the addedcost items, is a must on R- 1234yf systems just to match the performance of R-134a. Also required (and at extra cost) is an upgraded evaporator that meets a new SAE standard (J2842) to minimize the possibility of leakage of the flammable refrigerant from tubing corrosion or physical failure. Overall, R-1234yf systems are being designed with a combination of smaller but more efficient heat exchangers and the shortest possible routing of refrigerant lines, so refrigerant capacity is as small as possible. The engineering work has been part of an industrywide effort over a number of years to reduce the environmental footprint of a/c comprising both the global warming potential from refrigerant leakage and the carbon emissions from energy consumption. R-134a has a GWP of 1430 (vs. just 4 for R-1234yf), and the energy used by This is the refrigerant label for a Toyota Yaris with an R- 134a system. Note that the minimum refrigerant capacity is.33kg, or.73 lb., maximum is.39kg, or.86 lb. the system is only about 5% of total automotive fuel consumption. So we now have systems that hold as little as 11+ oz., and many with under 16 oz. This trend will accelerate, so that even at $100/lb., a system that has lost half its charge might require just 6 to 8 oz., or $40 to $50, of additional R-1234yf. That brings the refrigerant cost down to a level that if not palatable is at least more tolerable. Like the newest R-134a compressors, those for R- 1234yf have been engineered to hold most of the oil charge within the compressor housing. That both enhances lubrication and reduces the pumping losses from the conventional circulation of oil in the refrigerant. So a smaller amount of oil can be used, and if you check, you ll see some R-134a systems with as little as oz. of oil. The systems of years ago held up to 8 oz. or more. Are we likely to see European cars with R-1234yf reach these shores even late this year? Almost surely not, as the supplies will be tight and the refrigerant will be used only in new models that must meet the European Community mandate. But what you re more concerned about is the effect on you. Read the rest of this report for our assessment of the direct effect on the service industry. Incidentally, R-1234yf is still awaiting 28 April 2011 Circle #17

5 Circle #20 a final okay by the Office of Management and Budget. That s just a formality at this point, as R-1234yf has gone through all the legally required steps. The EPA expects the final rule from OMB this spring, the MACS convention was told by Yaidi Cancel, motor vehicle a/c specialist in the EPA s Stratospheric Ozone Protection Division. The Service Industry & R-1234yf The EPA requires that all refrigerants be recovered and recycled, and that each refrigerant system have unique service fittings. That also means new equipment with matching new service hose couplings will be required for this new refrigerant. SAE has developed a suite of new engineering standards for the new equipment to service R-1234yf systems. That equipment will be more expensive, primarily for two reasons: A recover/recycle/recharge (or even recover-only) machine must be designed to meet a number of stringent safety requirements, including arc-resistant switches and motors. Also, it must be engineered to vent any internal area into which R-1234yf might leak, so if a leak occurs within the equipment, the refrigerant is directed away from any possible ignition source. The same applies to other service equipment, including leak detectors and refrigerant identifiers. An R/R/R machine may be required to work only after the refrigerant in the vehicle system has been positively identified as R-1234yf. That s because there are SNAP List Use for Use for Contains Refrigerant Retrofit Factory Fill HCFCs R-416A FRIGC/FR X X Yes Free Zone/RB X X Yes Ikon X X No R-406A GH GGHG, GHG X3, X X Yes GHG-12, McCool, Auto Frost X3 GHG-HP X X Yes R-414A GHG-X4, Auto Frost, X X Yes Chill-It, Auto Frost X4 R-414B Hot Shot, Kar Kool X X Yes Freeze X X Yes GHG X X X Yes GHG-HP (HCFC Blend Lambda)... X X Yes SP34E X X No R-426A RS X X No HFC-134a X X No HFC-152a X No CO X No This is the current SNAP List, to which R-1234yf will be added and listed as okay for retrofit. Most of the refrigerants are blends that never caught on, as R-134a retrofit and recycled supplies of R-12 handled the existing fleet of R-12 vehicles during the 1990s and even today. R-152a is excluded as a retrofit refrigerant because of EPA restrictions on flammable refrigerants, and CO 2 (R-744) is excluded because of its much higher operating pressures. HCFCs are chemicals under an EPA phase-out schedule. 32 April 2011

6 considerable reasons for concern about refrigerant cross-contamination with R- 134a, which also was an issue between R- 134a and R-12. Assuming ID is mandated, the addition of an identifier will be necessary for the machine to operate. Although this aspect of the SAE standard for the R-1234yf machine has not been finalized, it s scheduled for inclusion in an update this spring. The identifier may be built in or available as a plug-in, such as to a USB port on the machine. If you re an a/c specialist who does a lot of work for car dealers and/or body shops, you probably see a lot of cars that are within the age range of the new-car warranty. So you may be assuming that you face an investment in a new recover/recycle/recharge machine and other equipment pretty soon. Our take: Yes, if you do warranty work for car dealers, since they ll be required by the vehicle manufacturers to restore the system with an R-1234yf charge. We re sure you noticed the $45 to $100 range for a pound of refrigerant and made the estimate that for a shop, the price is likely to be around $70/lb. Multiply by the typical 30 lbs. in a refrigerant jug and, uh-oh, do you need a small business loan just for the refrigerant? Hopefully not. The EPA had considered a minimum size of 20 lbs., but dropped that idea. So our guess is that we ll see returnable tanks of about 10 lbs., maybe even 5 lbs. But the plain fact is this: Once a vehicle leaves the plant and the factory gets its federal credit, that s it. Although the carmaker is obligated to continue with that refrigerant under warranty, that requirement doesn t extend to the aftermarket. So the carmakers will pay the dealers for their warranty costs for R-1234yf, but the independent shop and technically, even the car dealer with a customerpay job is free to do something else. If the evaporator must be replaced, the new one OE or aftermarket part must meet SAE J2842, and that SAE standard does not permit repairs. But more on this subject later in this report. The reason the refrigerant situation can change with customer-pay is because federal regulation of refrigerants is based on authority granted in the Clean Air Act to cover the phase-out of R-12. Yep, every subsequent refrigerant is legally just a replacement for R-12, and to be okay for use, the refrigerant must be put on what s called a SNAP List (Significant New Alternatives Policy), which means anything approved as an alternative for R-12. Each SNAP refrigerant must not affect the stratospheric ozone layer and is subject to usage restrictions, such as This is a prototype of a Neutronics identifier for R-1234yf recover/recycle/ recharge machines. The USB cable at right permits it to be plugged into one machine, then be removed for use with other R/R/R machines in a large shop. Lip 1 Lip 2 A double-lip shaft seal has helped reduce compressor leakage. Even triplelip seals are used in some applications to prevent refrigerant loss. 34 April 2011

7 those that require measures to prevent flammable concentrations of R-1234yf from accumulating in the passenger compartment for example, as the result of an accident or component failure. The only refrigerants that have a low GWP number, and therefore engendered OE consideration, are: R-134a, R- Circle #22 152a, R-744 (carbon dioxide used as a refrigerant) and now R-1234yf. Carbon dioxide systems, once considered a likely replacement, lost out because of the cost of components, durability and related issues. R-152a, although not highly flammable, is significantly more flammable than R-1234yf, and would have to be confined to an underhood refrigeration loop for safety. This is called a secondary loop system (heat exchange through an underhood chiller to a separate water/antifreeze solution circulated through the cabin for cooling). Interestingly, it s getting a new look because of its low cost vs. R-1234yf. Because both R-134a and R-1234yf are listed as acceptable for retrofit, there is legally no prohibition at this time on using the lower-cost R-134a as a replacement for R-1234yf. Is that what independent shops will do? The fact is that there s no performance difference if the substitution is made, and a realistic appraisal says that R-134a will be used. And unless the EPA mandates otherwise, the change will be legal. Furthermore, although the oil in an R-1234yf system will be a different PAG than that in an R-134a system, the R-1234yf PAG is backwards-compatible with R-134a systems, and the same is likely to apply to the polyol ester (POE) oil in electricdrive hybrids. That would mean that a shop could get by with a recover-only machine (that meets SAE J2851) for R- 1234yf, perhaps giving or selling the recovered refrigerant to a shop that recycles it. If the shop replaces the evaporator, it would be prudent for it to use one that meets SAE J2842 even if the system is retrofitted to R-134a. Otherwise, there might be legal liability if the system is ever changed back to R-1234yf and an issue arises as the result of an accident. So is that it? Should you figure on buying adapters we re sure will show up for R-1234yf-to-R-134a quick couplers? Then use R-134a in an R-1234yf system and everything will be legal and the customer will save money? Not so fast. First, the EPA might forbid that. It s still early in the game, so Drusilla Hufford, director of the Stratospheric Protection Division, could tell a MACS convention session only that we ll be looking into it. (See NewsBreak in the March issue for more details.) The new systems are designed to be super-tight, in some cases with new seals at the joints, improved double-lip (even triple-lip) compressor shaft seals and that new evaporator, which must pass a variety of tests, including corrosive salt spray. Most new cars are not expected to 36 April 2011

8 leak more than 10 to 15 grams of refrigerant per year, based on current data, and semihermetic electric-drive compressors used with hybrids may be even tighter. This is true for R-134a; it s surely going to apply to R-1234yf systems, because carmakers definitely do not want to have a system blow an expensive refrigerant charge under warranty. Let s consider a 16-oz. (455- to 475- gram) system that s cooling normally. There s unlikely to be a performance problem from refrigerant loss for at least seven or eight years, unless a seal(s) deteriorates faster than expected, or the system is compromised by other service. That would indicate to us that the first normal R-1234yf systems would not show up for aftermarket service until 2020, and they might need only a few ounces of the refrigerant. Even if the perpound price remains high, the cost for a small amount of R-1234yf is unlikely to be an issue, and it would probably be simpler to do a recover, recycle and recharge operation with R-1234yf than recover the entire charge, figure out where to unload it, connect adapters and recharge with R- 134a. These factors could lead the EPA to conclude that the OE changeover will be sufficient, considering EPA s limited enforcement capabilities. Bottom line: For the present and at least the foreseeable future, R-1234yf is an OE refrigerant and R-134a is what you ll continue to use, because not every manufacturer will aggressively move to R-1234yf. Down the line, however, the majority of R-1234yf systems that stay reasonably healthy might continue with R-1234yf for the rest of their lives, even with aftermarket service. Even if you hold off on servicing R- 1234yf, you ll need a new identifier; you don t want to contaminate your R-134a machine with R-1234yf or maybe something else if the system has received service from some other aftermarket shop perhaps one with shade tree instincts. So in addition to R-1234yf identifiers that plug into (or are built into) R/R/R machines, we ll also be seeing handheld R-1234yf-only and R-134a/R- 1234yf combo identifiers on the market. If certified to SAE J2912, these identifiers will have to ID refrigerants and air percentages with greater precision than existing R-134a identifiers now do. As R-1234yf systems come on stream, these identifiers might be your first purchase. If you already have a premium Neutronics Ultima ID identifier, you ll be able to send it in for a software upgrade that will identify R-1234yf by its chemical fingerprint the same idea as those fingerprints that indicate the different blend refrigerants. Without this upgrade, the identifier will display a meaningless message. This article can be found online at Circle #23 April