Preparing for another A/C season

April 18, 2016
With the rapid growth of vehicles using R1234yf and the increasing age of those first introduced, now is the time to prepare for the inevitable — and welcome that change with open arms.

While attending the annual Mobile Air Conditioning Society’s training event and trade show earlier this year, I came to a sudden realization. For the past few years, I’ve been reporting on the impending demise of R134a and those refrigerants that were going to be the likely replacements. And my, how time flies! Without retelling the entire story, let me give you the short version so that you may better understand where we are today – and what the impact on you and your shop will be.

A look back

Several years ago, the folks in Europe decided that R134a was a bad thing for the environment and passed a mandate requiring the OEMs to come up with an alternative if they wanted to continue to sell cars in their market. To our initial relief, these rules didn’t apply to the U.S. market. One rule that did apply, however, was the increasingly stringent CAFE requirements that OEMs had to meet. And one way to meet those requirements, in lieu of actual improvements in fuel economy, was to make other systems on their cars “greener,” and that included adopting these new refrigerants.

One highlight of the MACS event is the trade show exhibits, which were well attended this year.

Well, refrigerant (singular) may be more accurate. The one candidate that eventually rose to the top and gained nearly universal acceptance was one produced jointly by DuPont and Honeywell — HFO1234yf, also known as R1234yf. There is still much debate over the mildly flammable classification of the new gas, but OEMs across the board have spent millions on testing the safety of R1234yf under every conceivable condition they could imagine. Now, with three years and millions of miles of actual use on these systems, those dollars have proven to be a wise investment with no safety issues related to the new gas reported to date.

I only mention this issue to bring you this next tidbit of information. It is no secret in the industry that the good folks at Daimler took exception to using the new replacement, insisting it was unsafe and instead, continuing with its development of another alternative, CO2, also known as R744. The environmentalists love the idea, because the Global Warming Potential (GWP) of R744 is 1, the lowest rating you can get. But some members of the SAE Interior Climate Control committee point out that there are drawbacks to the use of CO2 in cars. One is the high system pressures needed for the system to work, nearly 10 times what you’re used to in today’s R134a systems. Another is the higher cost of producing these systems, and a third is the reported inefficiencies of the system when used in climates with high ambient conditions (like most of the southern United States). Regardless, Daimler has announced that it will start producing models equipped with R744 systems, starting with select MY2017 “E” and “S” class models offered for sale in Europe. Thankfully, though, there are no reported plans of sending these models to the U.S. market (yet).

ASA's Tony Molla was a featured speaker at the MACS confernce and shared his vision of the future challenges the industry faces.

So, is that it? Not quite. There were additional candidates and last year at this time, I was honestly concerned that we might have as many as five or six different refrigerants to deal with in our shops, including some potentially dangerous blends. Today I can share that the EPA has narrowed down the list of “acceptable use” refrigerants to four: R134a, R1234yf, R152a and R744. So which ones will you have to contend with?

The service picture today

The EPA has announced a “phase down” for R134a, with all new model passenger cars and light duty trucks to be equipped with an alternative by the 2021 model year. To date, in the North American market there are 18 OEMs using R1234yf in 47 different product lines. The market use is higher in Europe, with 33 OEMs offering 83 model lines equipped with the new gas. Considering that GM was among the first here in the states (and that that was three years ago now), the need for your shop to add R1234yf service capability has definitely arrived.

This simple aftermarket add-on pulses the compressor during initial start up to help clear it of any excess liquid and is available for select models.
Every manufacturer that makes an RRR machine was represented, highlighting their R1234yf offerings for attendees.

For those of you who lived through the transition from R12 to R134a, you’ll be happy to know that those in charge learned from that experience. R134a is not being phased “out” but “down,” and that’s an important distinction. First, R134a will be available as long as there are vehicles on the road equipped with it. Second, there will be NO requirement to retrofit an R134a car to one of the new alternatives. Thank God, too, because the leading replacement choice (R1234yf) isn’t cheap.

With some models nearing the end of their warranty periods, it is time for your shop to consider investing in the equipment you’ll need to properly service these systems. Of course, that means a new Recovery/Recycling/Recharging (RRR) machine will be on the top of your list. Because of the mildly flammable classification and the high cost of the refrigerant, these machines differ in design and function from the RRR machines you are used to, even if you’ve invested in an R134a machine certified to the J2788 SAE standard.

R1234yf machines require you to first perform a refrigerant identification test prior to recovering the vehicle’s charge. We’ve been promoting that as a best practice for a number of reasons and still do, even if you’re servicing R134a. Once you’ve completed that phase and performed whatever repair you needed to make, these new machines will then perform a few leak tests before allowing you to recharge the system. Specifically, a vacuum hold test is first performed and if that passes, the machine will allow a charge of 15 percent of the specified charge for that system. Then a pressure hold test is performed. If that passes, you can charge the rest of the way, but if not, you’ll need to find that leak before you can return the car.

That means no system top offs and no recharging a customer’s system unless he’s prepared to fix the leak that caused the loss in the first place.

Other service notes

Also discussed at the MACS conference was an SAE letter sent to the EPA recommending that technicians currently certified under Section 609 of the Clean Air Act be required to recertify. This is not the same thing as your ASE A7 certification; this is the little card you are required to have in your wallet saying that the EPA certifies you in the safe handling of refrigerants. Many of us took the certification decades ago and have never updated it, and the safety concerns surrounding the service and repair of R1234yf and R744 systems certainly need to be addressed. The letter further recommends that the certification be updated periodically, just like your ASE certs are.

We've encouraged you to always identify what's in a system before you recover it into your equipment. This model indentifier is inexpensive and could save you money in the long run.

Don’t have your Section 609 certification? It’s not that big a deal and is available from several sources. Getting caught working on an air conditioning system without it, though, could cost you and your shop plenty.

Not only are there new gasses you need to know about, but system designs have changed significantly over the last several years. Among the changes is the adoption of lower refrigerant charges. That means a few things for your service process. First, recovery and recharging must be done more accurately. Gone are the days of relying on gauge readings to know when you’ve properly charged a system, as are the days of using a set of gauges and scale alone. Second, the need to find and repair even small leaks is important to the continued efficiency of the system and the continued happiness of your customer.

In addition to lower refrigerant charges are lower oil charges. The old rules of thumb we used to use when replacing a system component (2 ounces for an evaporator or condenser, for example) are no longer applicable. Too much oil in the system will have a dramatic effect on system performance and that includes any oil you add when adding a leak detection dye. You must use the OEM-specified oil-balancing procedure to insure proper lubrication and operation. It was also noted that some RRR machines are removing excessive oil during the recovery process. It is imperative that you measure what is removed and replace with fresh oil of the same type when charging the system back up.

Speaking of leak detection dye, many new compressor designs retain the majority of the oil charge in an internal sump. These systems pass very little oil along with the refrigerant charge. That keeps the oil off of the innards of the heat exchangers, preventing heat transfer losses caused by the oil coating. At the same time, though, it makes it more difficult to circulate the dye through the system. If you’re hunting for that small leak, you may need to tell your customer to drive the car for a few days to allow the dye time to get around.

Have an RRR machine that is not rated for hybrid use? This product can help you prevent accidental contamination if your hybrid services are few and far between.

But wait a minute — I can’t recharge an R1234yf system that doesn’t meet the leak test. How do I know there’s a small leak present before I recover the charge? Good question! See what I mean about rethinking your service processes? Hopefully, help for this question and others is on the horizon. Some members of the SAE committee have requested that the committee consider establishing standards for air conditioning service. If undertaken, it will set standards for best practices, as well as strive to standardize component names, Diagnostic Trouble Codes (DTCs) and diagnostic processes.

Let’s not forget about the hybrids!

Servicing hybrid air conditioning systems that use a high-voltage electric compressor or combination HV/belt-driven compressor is not new news. But it is worth pointing out for those of you who have yet to tackle one of these jobs the importance of avoiding any possibility of contaminating the system with PAG oil. It’s easy to do if you’re using your RRR machine to inject oil into your customer’s system. Even that relatively small amount that remains in the hoses can cost you a ton of money if it gets in a system requiring POE oil. Understand that PAG oil is conductive and even a small amount could set an HV Leak code. If the compressor has engaged and run, that means you’ll be replacing every part in the system to correct the code. Explain that to your customer!

Trade show tidbits

A trip to MACS wouldn’t be complete without a few turns around the trade show. One product that caught my eye pretty quick was an offering from Four Seasons called “The Deslugger.” It’s an aftermarket solution to an increasingly common problem – compressor damage caused by oil and liquid refrigerant collecting on the compressor, especially on those models where the compressor is mounted low on the engine.

It's only a 10 ound R1234yf container, but it will set you back quite a bit. The high cost is one reason the RRR machines won't let you charge a leaking system.

The combination can cause hydraulic lock on initial compressor engagement, and if you’ve ever seen the insides of an engine that suffered a similar fate, you know what the inside of the compressor looks like immediately after. The Deslugger is an electronic compressor “timer” that pulses the compressor clutch multiple times on initial engagement to help gently purge an excess liquid before full engagement is allowed. Currently, there are three part numbers available: P/N 36140 for 2002-2006 Honda CRVs with scroll compressors, P/N 36141 for GM vehicles using the Denso 10S compressor, and P/N 36142 for Chrysler Voyagers and Dodge Caravans also using the Denso 10S compressor.

Another product that looks like a time saver is the blend door repair kit offered by AirSept. This kit cuts down the time needed to replace broken blend doors on 2006-2009 Equinox and Torrent models, 1997-2004 Ford F-series pickups, 1999-2004 Jeep Grand Cherokees and is also available for the driver side doors on 2005-2007 Explorers and Mountaineers. Another product from this same vendor is the RecycleGuard, a filter that can be used in line with your existing RRR machine to capture any sealants that may be present in the system. And if you have a lot of DIY customers in your area, take a look at what they’re buying at the local big box store. In my area, at least, every little can of DIY R134a has sealant included. The last offer from AirSept I want to be sure is on your radar is their ChargeGuard product, a system for you guys who only do occasional hybrid service and want a way to insure that you don’t accidentally contaminate the system with PAG oil.

Of course, there were RRR machines galore on display, including the latest from MAHLE, Robinair, Yellow Jacket and FloDynamics. If you’re in the market for a new machine, these companies had a variety of offerings to cover nearly any budget.

RRR machines are available in a variety of styles and features. There's one to fit your shop's needs and budget.

In addition to all these great products were a variety of service tools, leak detection dyes and sniffers, even ultrasound diagnostic aids. Unfortunately, (and with apologies to all the vendors that were on hand) space does not allow me to mention them all.

For the last few years, I’ve been telling you that new refrigerants and new service challenges were on the horizon, and I advised you to hold off on any major investments for a bit unless your shop serviced area body shops or dealers were few and far from your customers. With the rapid growth of vehicles using R1234yf and the increasing age of those first introduced, now is the time to prepare for the inevitable — and welcome that change with open arms.

About the Author

Pete Meier | Creative Director, Technical | Vehicle Repair Group

Pete Meier is the former creative director, technical, for the Vehicle Repair Group with Endeavor Business Media. He is an ASE certified Master Technician with over 35 years of practical experience as a technician and educator, covering a wide variety of makes and models. He began writing for Motor Age as a contributor in 2006 and joined the magazine full-time as technical editor in 2010. Pete grew the Motor Age YouTube channel to more than 100,000 subscribers by delivering essential training videos for technicians at all levels. 

Connect with Pete on LinkedIn.

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