Tool Q&A: How to prepare for the new A/C refrigerant
It seems like everywhere you look these days, you hear about global warming and its effects on our beloved planet earth. Although some of the discussions surrounding this topic can foster a good deal of controversy, you can be sure that any legislation driven by global warming concerns is going to have an effect at the shop level.
To that end, the industry is on the brink of its second major change of factory fill for refrigerants in mobile air conditioning systems. It’s hard to believe that R-134a has been with us since 1995, but you might as well consider it the lame duck of refrigerants as the industry prepares for R-134a’s successor, a refrigerant designated as HFO-1234yf, or simply R-1234yf.
In this month’s Tool Q&A, we address some of your most common questions regarding A/C service as it looks today with R-134a and how it’s likely to transition with the dawning of a new refrigerant.
Q. We originally switched from R-12 to R-134a because R-134a didn’t deplete the ozone layer, so why are we switching again?
A. Although R-134a was chosen as R-12's successor due to having non-ozone-depleting properties, new environmental concerns would eventually surface that cast a shadow on the future viability of R-134a. With international emphasis now on global warming, it became clear that R-134a's high global-warming potential made it an unlikely candidate to be the refrigerant of choice headed into the future. Accordingly, research began to find a more environmentally friendly alternative refrigerant. At first, it appeared as though CO2, also known as R-744, would be R-134a's successor. However, R-744 operates at much higher pressures and has a lower thermodynamic efficiency (ability to displace heat) than R-134a. These factors opened the door to another R-134a alternative, designated as R-1234yf. This new refrigerant has vapor-pressure performance that very closely matches that of R-134a, yet with a lower net global-warming potential than R-744. These factors put another couple of checkmarks into the plus column for R-1234yf. This new refrigerant is now poised to become the replacement for R-134a and cars filled with the new refrigerant will soon be headed your way.
Q. Are there any downsides to this new R-1234yf refrigerant?
A. At present, there are two. First, R-1234yf will cost roughly ten times more than R-134a. Keep in mind, though, that this is a preliminary estimate. Like anything that’s manufactured, costs tend to come down once an industry gears up and gets into full production. Second, R-1234yf has mild flammability traits when under pressure, and we stress mild. These traits are accounted for in upcoming training and certification programs for this new refrigerant.
Q. Our shop did quite a few retrofits, converting from R-12 to R-134a. Will we also be able to retrofit R-134a systems to R-1234yf?
A. No, retrofitting R-134a systems to R-1234yf will not be allowed. First of all, it doesn’t make economic sense to switch to a refrigerant that’s estimated to be ten times as expensive as R-134a. Second, because of R-1234yf’s mild flammability characteristics, the evaporator for systems containing this new refrigerant have to be sturdier than for previous refrigerants. That’s why SAE has a standard in the works for evaporators in R-1234yf systems, designated as J2842.
Q. How long do I have to prepare for servicing this new refrigerant? In other words, how long do I have to gear up for my shop and technicians?
A. General Motors will be the first auto maker to feature HFO-1234yf in 2013 model year Chevrolet, Buick, GMC and Cadillac models. You can expect other car makers to make similar announcements soon on their rollout plans for the new refrigerant.
Q. How much of an impact will servicing cars with R-1234yf have on my current A/C service equipment?
A. In a nutshell, R-1234yf will have a big impact on your tool and equipment requirements in the not-too-distant future. As examples, the Society of Automotive Engineers is currently crafting standards for new equipment. SAE standard J2843 establishes specifications for recovery/recycling/recharging equipment for R-1234yf refrigerant. The key requirements of J2843 include new hose connections compliant with R-1234yf-specific service fittings, reduced sparking of electrical components and increased cabinet ventilation to offset mild flammability concerns associated with R-1234yf. Refrigerant handling equipment meeting J2843 will also prevent recharging a leaking system using both vacuum and pressure leak detection. Refrigerant cylinders for R-1234yf will also be colored white with a red band as a visual cue to their content. SAE also has a “piggyback standard” in the works for the internal refrigerant identifier function of J2843-compliant recovery/recycling/recharging equipment, which will be published as J2927.
Q. We run a salvage operation and have performed recovery-only of the refrigerant in the A/C systems of salvaged vehicles. Are there any considerations for this with this new refrigerant?
A. Yes, just like with R-12 and R-134a, recovery-only equipment will also be able to be used on R-1234yf systems. SAE is developing a standard for this application as well, known has J2851. Equipment meeting this standard will be required to have many of the same properties as recovery/recycling/recharging equipment. In addition, J2851-compliant recovery-only equipment will be able to recover refrigerant from an A/C system, even when a leak exists in that system.
Q. How will I know if a car is equipped with HFO-1234yf?
A. The U.S. EPA requires unique fittings and labels for all refrigerants to increase the likelihood of proper refrigerant service and to reduce the chances of refrigerant cross-contamination. Under the proposed revisions to SAE J639, the system charge label clearly shows “R-1234yf” as the refrigerant and specifies the amount of charge and associated refrigerant oil to be used. In addition, the label also displays icons alerting you to R-1234yf’s mild flammability concerns and the need for technician training and certification. Of course, with every new refrigerant, comes an additional chance of system cross-contamination. So, no matter what a label states, it’s never a guarantee that the system contains that refrigerant either fully or partially. As with any system, a refrigerant identifier should also be used to determine what’s in a system.
Q. Will this new refrigerant also affect what kind of leak detector I can use?
A. Yes, R-1234yf will require more sensitive “sniffing” technology than what’s currently incorporated inside R-134a leak detectors. This new generation of leak detectors must meet SAE standard J2913, which defines the performance criteria for electronic leak detectors. Although not yet detailed, it’s likely that SAE will either generate a new standard or revise an existing standard on the technician procedure for using an electronic leak detector. Such standards have been issued in the past for other electronic leak detectors intended for R-12 and R-134a refrigerants.
Q. All the technicians in our shop have current certifications for performing mobile air conditioning service. Will we have to do this all over again for new vehicles with the new refrigerant?
A. Although R-1234yf refrigerant and its related equipment certainly speak volumes about upcoming changes in A/C service, EPA has not yet issued new requirements for Section 609 training and certification programs. SAE standard J2845, “Technician Training for Safe Service and Containment of Refrigerants Used in Mobile A/C Systems,” spells out certain requirements for technicians as a result of a heavy push by the auto makers. Among other things, J2845 focuses on:
- Understanding how R-1234yf and R-134a differ
- Best practices for system service
- Recognizing fittings/labels and refrigerant tanks
- Using refrigerant identifiers
- Using leak detectors
- Maintaining safety through vehicle manufacturer recommendations and using the proper recovery/recycling/recharging equipment
Again, although a training and certification path has not yet been established by EPA, there are a couple of likely plans. The first plan may simply include a separate program designed specifically for R-1234yf systems with training and certification in that regard. Another plan may include simply adding content for R-1234yf to existing Section 609 content so the program becomes all-encompassing for all motor vehicle air conditioning systems.
Q. Can you use the same R-134a A /C machine on a hybrid and a regular car? Or is the oil not mixable?
A. Although the same type of refrigerant handling machine can be used on both regular and hybrid cars (since they both use R-134a refrigerant), you should use separate machines to prevent mixing of the oils used in each system. Hybrids use special, electrically insulated oil that cannot be mixed with the standard refrigerant oil used in regular cars.
Charles Kettering, one of GM’s most acclaimed engineers, once stated, “Nothing is constant, but change.” There’s plenty of it headed your way that will affect everything from your refrigerant handling equipment, to your shop, up to and including your training and certification for mobile air conditioning systems. While it’s true that the EPA still has to put the final touches on the regulatory side of things, the stage is set for the biggest change to A/C service since the adoption of R-134a. Stay tuned to PTEN for more details as they develop.
