Are You Ready for New Refrigerants?

Posted 1/14/2010
By Ward Atkinson

Editor's Note: An expanded version of this article appeared in the May 2009 issue of ACTION, the membership magazine of MACS Worldwide.

It's been a little more than a decade since CFC-12 - which was sold under the brand name of Freon 12 - was banned in the United States and other countries because it damaged the ozone layer. And now the mobile air conditioning industry is facing the replacement of its replacement, HFC-134a. This time the refrigerant replacement challenge may be greater, and the issues surrounding the last changeover need to be addressed.

During the change from R-12 to R-134a in the early 1990s, global consensus was reached quickly, and the industry focused on implementation. With the current change, the first problem is that the focus has been on a replacement refrigerant for Europe only. Development of six alternative refrigerants has taken place over the past 10 years, and even today there is no consensus on a single refrigerant for global use.

The European "F-gas" law will soon require motor vehicle air conditioning systems (MVACs) to use refrigerants with a global warming potential (GWP) of less than 150. Much industry effort has been spent to evaluate possible replacement refrigerants. In the United States, legislation in California includes provisions for credits for the use of low GWP refrigerants to encourage their use, and other states may adopt similar laws.

Carbon dioxide (R-744) and HFO-1234yf will both meet the European requirements. The use of R-744 requires an entirely new MVAC system due to higher-operating pressures. HFO-1234yf, a mildly flammable chemical, also requires system design considerations but in general can use current HFC-134a system component technology since it has similar operating pressures.

In February 2009, David D. Doniger, policy director of the Climate Center of the Natural Resources Defense Council (NRDC), sent a letter to several industry leaders and the Environmental Protection Agency (EPA). In his letter, he wrote:

"Specifically, NRDC wants to work with the MVAC community on measures to:

• Phase-out HFC-134a in mobile air conditioning on a specific schedule,

• Contain, recycle, and destroy CFC and HFC refrigerants used in existing and future cars,

• Bar manufacture and sale of nonreturnable cans of refrigerant,

• Restrict the sale of returnable refrigerant containers to certified technicians working with the latest recovery/recycle equipment.

'This industry's leadership in addressing the dangers of climate change can be an inspiration and a model for others. We have worked together before. I look forward to working with you again to meet this challenge."

Some perspective

The phaseout of CFC-12 was based on its contribution to depletion of the earth's ozone layer. Today, international attitudes have changed to a focus on global warming issues, and the European Union has already started the elimination of HFC-134a as a refrigerant. With other organizations and regulatory agencies considering continuing this trend, the problems experienced with the CFC-12 to HFC-134a transition must not be repeated if a true environmental and consumer benefit is to be achieved.

In North America, replacing CFC-12 created major problems. The vehicle manufacturers developed retrofit procedures, and in some cases provided kits to convert CFC-12 systems to use HFC-134a.

Only substitute refrigerants listed as acceptable by the EPA can be legally installed in automotive A/C systems. The EPA had listed more than 10 different refrigerants under the Significant New Alternatives Policy (SNAP) as replacement refrigerants for CFC-12 MVAC systems. Many contained HCFCs.

Further, each substitute refrigerant required unique service fittings. Since replacement refrigerants cannot be vented to the atmosphere, they also required specific recovery equipment for which there were no standards or equipment except for HFC-134a.

Also, the U.S. Clean Air Act mandated recovery and reuse of CFC-12 and restricted its purchase to certified technicians. But the new refrigerant, HFC-134a, could be purchased and used by anyone - professionals or do-it-yourselfers (DIYers).

Non-original equipment manufacturer sources promoted numerous refrigerant replacements, including flammable alternatives such as propane. The use of these non-approved products and service procedures resulted in many problems, including cross-contamination of vehicle systems and damage to recovery and recycling service equipment.

These situations resulted in additional cost to the consumer as well as the service industry, and did not benefit the environment. In fact, since the EPA allowed multiple refrigerants for MVAC, the result was many opportunities for contamination of systems and equipment. As well, consumers incurred additional repair bills after having other refrigerants charged into their CFC-12 systems. Since specialized recovery or recycling equipment was not available for each alternate refrigerant other than HFC-134a, there was the added potential of releasing the refrigerant to the atmosphere from MVAC systems.

The next changeover

While the impact of replacing HFC-134a can be seen through the lens of history, the magnitude is much greater. The world vehicle population has increased and air conditioning has become nearly standard on all vehicles worldwide.

Present systems are designed and tested only for use with HFC-134a, and with specific internal lubricants. Present systems are mature, and in recent years, the industry has improved mobile vehicle air conditioning system design to be more energy efficient and have less refrigerant loss. Current MVAC system refrigerant emissions average about one-half ounce (15 grams) per year. The industry has also reduced the amount of refrigerant used in a system.

In model year 2000, the average single evaporator system charge was 26.9 ounces (763 grams); by 2004 it was 24.3 ounces (689g) and for 2009 models, the average is 22.2 ounces (629g). The industry is using less refrigerant in every passenger vehicle and containing it better.

Any replacement refrigerant should be evaluated on its total environmental footprint and consider the best scenarios for replacing HFC-134a including cost for the consumer, new vehicle production, the existing HFC-134a fleet and effects on the service sector.

For many reasons, it is advisable to allow the natural phaseout of the HFC-134a fleet instead of a legislated phaseout. When our industry replaced CFC-12 in the U.S. fleet, HFC-134a was in production before any regulatory deadline. Presently, that cannot be said of any proposed substitute refrigerant. When evaluations are completed on replacement refrigerants, they should be considered for an orderly and reasonable phase-in without a mandatory deadline.

The SAE has addressed the new design criteria, service equipment and technician certification that will be required by a new refrigerant. In addition, the U.S. EPA has worked with various state regulatory statutes to allow the use of these new refrigerants in new vehicles.

Avoiding problems

Today's industry knowledge should guide the choices for the future. While it is obvious that a present-day system cannot be converted to use high-pressure carbon dioxide, an existing system might be retrofitted to use HFO-1234yf with proper safety modifications. But the chance for conversion to other refrigerants also exists and becomes even more likely if a new refrigerant is more costly.

It should also be noted that the history of typical consumer attitude and HFC-134a usage indicates that recharging, but not repairing, a leaking system is still very common. This attitude of tolerating leaking systems has led to the present atmospheric concentration of HFC-134a and motivated Europe to legislate against its continued use.

Even professional service facilities have frequent consumer requests to only add refrigerant and not repair leaking MVAC systems. In 2003, the MVAC industry consumed 84 million pounds of refrigerant. Of that year's total use, roughly 26 million pounds of refrigerant was sold in "small cans" for consumer use. Between professional and DIY'er uses, it is possible that nearly 25 million pounds of refrigerant could have been directly released to the atmosphere by leaking MVAC systems and faulty service practices.

The way forward

It is certain that a new refrigerant is coming, and that a cost-effective and environmentally acceptable process is possible without mandatory legislation. It will require cooperation and commitment by every stakeholder from manufacturer to consumer. It will require aggressive support by government agencies at the national, state and local levels and a mutually agreed timetable.

An industry-led cooperative phaseout of HFC-134a will also require unified government and legislative support including:

• restricting retrofitting of the HFC-134a fleet and allowing continued use of that refrigerant until the vehicle is salvaged.

• requiring that all new MVAC systems meet industry and SAE standards for the refrigerant in use.

• allowing only the use of replacement refrigerants accepted to the EPA's SNAP list and meeting industry and SAE specifications,

• restricting sale of all refrigerants to only qualified and certified personnel,

• requiring certified technicians for servicing of any MVAC system,

• requiring appropriate and approved MVAC service equipment for both existing and replacement refrigerants.

Regardless of the substitute refrigerant(s) chosen, technicians will need to be aware of workplace procedures for handling and storing refrigerants safely, including OSHA and DOT requirements. Additionally, education will be required to reduce charging of leaking systems (topping off) by either a DIY'er or a service facility. Even more training must be provided to technicians working on hybrid vehicles to prevent introducing electrical hazards and system failures.

Emissions can also be reduced by revising present regulations to restrict the sale of HFC-134a. Only certified technicians should be allowed to purchase and use refrigerants in both the mobile and commercial service sectors. These measures may actually provide additional environmental benefits more quickly than phasing out R-134a and creating new issues with retrofitted systems.

Ward Atkinson is the Mobile Air Conditioning Society's technical adviser, and he is also chairman of the SAE International's Interior Climate Control Standards Committee. More information on new refrigerants is available from MACS Worldwide through www.macsw.org.