Automotive air conditioning is changing at a rapid rate. Environmental and regulatory issues will pose new challenges for service facilities and technicians. Here’s a look at what’s “hot” in cooling.
Air conditioning is one of the most technically complicated and politically sensitive issues faced by automotive service facilities. The desires of a vehicle owner to be comfortable must be balanced by the mandate to meet environmental regulations and the shop’s need to turn a profit.
Over the last year or so, many factors have affected the industry. Environmental regulation and responsibility are being pitted against optimum performance and operational economy. New design and testing standards are being put into place. New types of equipment are being manufactured to meet the new standards. New types of refrigerants are being considered to meet environmental needs.
As the industry continually changes, it becomes harder for technicians and shops to keep up with the rules and regulations. Here, we present a primer on the most recent developments that will soon affect the industry, your customers, their vehicles and you.
The Society of Automotive Engineers (SAE) has recently established new standards dealing with automotive air conditioning. These SAE “J” standards were developed to improve quality, accuracy, uniformity and compliance with environmental regulations.
You’ll soon begin be seeing references to these new standards on A/C products, tools and equipment, so you’ll need to know what they mean and how they apply to the vehicles you service and your shop.
Because these standards and terms can create some confusion, we will briefly detail the new standards so you can be aware of what they mean to you and the A/C systems you’ll be working on.
J2788 Standard for Recycling Machines
Last December, SAE issued a new standard to establish minimum equipment performance requirements for recovery and recycling of R-134a that has been removed from, and is intended for reuse in, mobile A/C systems. J2788, which will go into effect later this year, mandates that A/C recycling machines recover at least 95% of the refrigerant to minimize atmospheric emissions. The old standard was 75%.
Another facet of the standard states that recharging accuracy must be achieved to within +/- 1/2 ounce, down from the previously-allowable one ounce.
All recycling machines manufactured after November 1, 2007 must meet this standard, so keep that in mind as you consider purchasing new equipment.
J2776 Standard for Refrigerant Purity
Issued in October, 2006, this standard covers the purity of the R-134a refrigerant and the cleanliness of the container. It requires refrigerant manufacturers and packagers to meet tight levels of quality to avoid vehicle systems from being contaminated by impurities in the refrigerant or containers.
Later this year, when the standard goes into effect, you’ll want to start checking the labels on the containers of refrigerant you receive to ensure you’re servicing with the highest quality of refrigerant possible.
Remember, R-134a containers are supposed to be light blue in color, not green (R-22) or white (R-12). The best advice is to purchase a name-brand product from a reliable source. Using Genuine Subaru R-134a Refrigerant is the best way to ensure you have the highest quality refrigerant.
J2971 Standard for Minimum Performance Criteria for R-134a Refrigerant Electronic Leak Detectors Issued just this past January, the new standard applies to electronic probe-type leak detectors used to identify R-134a refrigerant leakage in mobile air conditioning systems. It establishes greater minimum performance criteria for these leak detectors in the underhood area, where fumes from gasoline, oil and other chemicals often trigger false readings.
The new standard requires detection of leaks down to 1/7 ounce from a detection probe moving past the leak at three inches per second, approximately half of the former standard.
This article was written to reveal the newest A/C products. Subaru tools not available at local dealers or as requested from SOA.
At the current time, those criteria are being studied by tool manufacturers so that they can make their tools compliant with the new standard that will go into effect around the end of the year.
Again, this is a significantly important feature of any electronic detection tool you may consider purchasing in the future.
J2670 Standard for Stability and Compatibility Criteria for Additives and Flushing Materials
This standard was issued in mid-2005, but is only now reaching full effect in the industry. It applies to any and all additives and chemical solutions intended for aftermarket use in the refrigerant circuit of vehicle air-conditioning systems. It provides testing and acceptance criteria for determining the stability and compatibility of additives and flushing materials (solutions) with normal A/C system materials (refrigerant and lubricant) and components, that may be intended for use in servicing or operation of vehicle air conditioning systems.
The standard does not address compressor lubricants or dyes. It only pertains to aftermarket additives and flushing chemicals.
The J2760 standard should be a consideration when choosing additives or flushing materials in your shop. Products that meet the standard will most likely include a compliance reference to the standard on the label or in marketing materials.
J2788 Compliant Recovery & Recycling Equipment
Robinair’s new Cool-Tech Model 34788 HFC-134a refrigerant recovery and recharging unit was the first on the market that is fully compliant with the new SAE J2788 requirements, and is also said to be compatible with both conventional A/C systems and hybrid vehicles that use electrically driven compressors. Other J2788-compliant equipment will be available soon.
A refrigerant identifier is rapidly becoming a necessary piece of equipment in any shop that performs air conditioning service. These devices accurately and quickly identify the contents of a vehicle’s A/C system or a refrigerant tank.
An identifier will help avoid the accidental use of impure, improper, mixed or contaminated refrigerant. Installing such products can severely damage a vehicle’s A/C system and spell real problems for the shop.
The latest versions of refrigerant identifiers not only identify the contents of the system or tank as R-134a, R-12 or R-22, but also the percentage of each. They can also measure the percentage of air in a system or tank. Most identifiers feature a “Go” or “No Go” indicator for a 98% purity level.
The most sophisticated versions also detect any hydrocarbons, such as propane or butane, and feature a visual or sonic alarm to warn the operator. Some even offer a printout feature.
Electronic Leak Detectors
Finding escaping refrigerant with an electronic leak detector takes a little more time, patience and training than the fluorescent dye method does. Under a UV light, dye is readily apparent, but it can cause the compressor oil to break down, resulting in compressor damage. Another problem with dye is that it may still be present at leak areas from a previous service, causing you to draw misleading conclusions.
Subaru and most of its A/C component suppliers do not approve the use of dye to locate leaks, so, unless a Subaru vehicle arrives at your shop with dye already injected into the system, an electronic leak detector should be used.
These detectors require the technician to slowly move the sensing tip around suspected leak areas, including valves, joints, ports, compressor shaft seals and connectors. Experience with one lessens the time needed for good results.
Most electronic leak detectors feature visual and audible leak alarms that are activated when the sensor tip approaches a leak. A LED visual indicator is helpful for working in the noisy shop environment. A variable-range audible alarm is also valuable. A balance control to help eliminate false alarms from other underhood gases and chemicals is definitely a plus.
Better quality detectors feature “corona” technology that uses a high-voltage system to create an electronic arc, which senses the presence of refrigerant. These sensor tips must be replaced periodically as they eventually lose sensitivity.
New models of electronic “sniffers” are being designed and manufactured to meet the new SAE J2791 standard described previously. These new devices will be much more sensitive, easier to use and provide quicker results.
Many new state regulations have recently been enacted and are being enforced. Rather than listing the lengthy, possibly not up-to-date regulations in individual states, we suggest that you make yourself aware of the latest regulatory information in your state.
The following states have banned the use of flammable refrigerants in automotive air conditioners: Arkansas, Arizona, Connecticut, Florida, Idaho, Iowa, Indiana, Kansas, Louisiana, Maryland, Montana, Nebraska, North Dakota, Oklahoma, Texas, Utah, Virginia, Washington, Wisconsin, and the District of Columbia.
New Refrigerant on the Horizon?
As the quest for environmentally-safer, more efficient air conditioning systems continues, many alternative refrigerants and trouble-free systems are being considered.
R-134a does not damage the atmosphere’s ozone layer, but still poses a threat as a greenhouse gas with a high global warming potential (GWP, meaning it holds heat) — its warming factor is more than a thousand times greater than that of carbon dioxide.
Europe and Japan, with densely populated urban areas, are leading the efforts to reduce pollution and emissions, and find long-term answers. Each region wants a new refrigerant in use by the end of the decade.
At this time, the most likely candidates for global A/C systems are HFC-152a, a substitute for R-134a that would work in present systems, or carbon dioxide (CO2) that would require the engineering and manufacture of a completely new type of system. In Europe, the favored medium is HFC-152a, while Japan is lobbying for the use of carbon dioxide. Neither is perfect.
HFC-152a, known as difluoroethane, can be used in present systems without any special preparation. It has very low global warming potential and is less flammable than most hydrocarbon compounds. It has better cooling ability than R-134a with less product usage. HFC-152a has a much lower effect on global warming. It is, however, slightly flammable.
Carbon dioxide, or CO2, has no adverse effect on the environment and is very inexpensive to create and package. However, because it condenses, it requires high pressure systems (up to 400 psi on the low side and up to 1,800 psi on the high side). The design and manufacture of high pressure components and fittings will be required. Leak detection poses a problem because CO2 is present in the air all the time (humans and animals exhale it).
Helpful A/C Information
The Mobile Air Condition Society Worldwide (MACS) offers updated versions of its very helpful Recommended Service Procedures Guide and Recommended Inspection and Preventive Maintenance Guide. Both can be downloaded at the MACS website: www.macsw.org. These documents reflect the latest practices in automotive air conditioning service and will be updated as future changes take effect.