A/C Service: The Heart of the Matter
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A/C Service: The Heart of the Matter

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The heart of the business, feel the heart beat, he has a good heart. These familiar thoughts and sayings all refer to the same thing. Whether it is a figurative or literal reference, the message is the same. There is always a central and irreplaceable part or component or, sometimes, person to all things. This is true whether you are speaking about a sports team, a business, a body or even an automotive repair shop.

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This is also absolutely true when speaking about the tools and equipment needed to repair and service vehicle air conditioning systems. The “heart” of this activity is the Recovery/Recycle/Recharge machine. While all the tools you use every day are important, you can’t effectively, accurately or LEGALLY service A/C systems without the R/R/R A/C machine. Recently, the A/C heartbeat had a big blip in its rhythm. A/C recovery machines have been pretty consistent and unchanged for quite a few years. The last major change to the machines was the evolution to R-134a several years ago. These machines have gotten better every year as manufacturing and technology has improved — but the changes were small.

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Several years ago the EPA and MACS (Mobile Air Conditioning Society) began studying the need for alternative refrigerants. The general thought was that R-134a might not be the long-term solution for several reasons.

As an alternative to phasing out R-134a, the decision was made to improve the processes, systems and equipment used to service R-134a. These decisions included improvements to reduce the total volume of refrigerant used in vehicles, and smaller components and systems. The smaller systems are less burdensome on a vehicle’s engine, subsequently improving fuel efficiency.

A New Era
But now there is a major change that directly affects all of us in the automotive aftermarket and especially technicians and shop owners — it is the implementation of a new SAE specification: J-2788. This specification is designed to require Recovery/Recycle/Recharge machines to be much more effective, accurate and efficient in the way they process refrigerant.

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This specification has three main areas of focus to achieve the goal: Percent of Refrigerant Recovered, Charge Accuracy and Shop Safety-Filter Management.

All the tests and the certification process were designed using one test vehicle — a 2005-’07 Chevrolet Suburban with a dual air conditioning system. This vehicle has a standard system capacity of 3 lbs. of refrigerant.

The percent of recovered volume portion of the specification is the most important in terms of achieving the goal of reducing the occurrence of venting refrigerant to the atmosphere. The spec says that the machine must recover 95% of the system volume within the first 30 minutes of the recovery process.

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Charge accuracy has become more important on the new low-volume systems. There are many cars being produced now with system volumes as low as 1 lb. or less! The new specification requires that the charge accuracy must be +/- 1/2 oz. This specification is a difficult one to obtain and has forced manufacturers of recycling equipment to improve the quality and resolution of the scales that they used prior to the new J-2788 spec.

The final portion of the new regulation has to do with shop safety. The concern is that in many cases shops fail to change the filter on the recycler frequently enough (if ever!). There is some evidence that the dirty or obstructed filter can result in system failures and possibly injure operators of the equipment. In order to prevent this problem, the specification requires that the equipment have an automated system to keep track of the volume of refrigerant filtered and notify the operator of the need to change the filter. If the technician fails to change the filter, the equipment must shut itself down until the filter is replaced.

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There has been some confusion surrounding the dates and deadlines for the SAE J-2788 specification. As of this printing, we believe the following dates to be accurate:

  • All R-134a machines with the current J-2210 specification being manufactured will become obsolete and illegal to be manufactured after December 2007.

  • Manufacturers and distributors will have through April 2008 to sell units that comply with the current specification (J-2210) to service shops.

  • Units in the field prior to May 2008 that comply with SAE J-2210 can be used through their “useful life”

  • The EPA does not currently have plans for a forced obsolescence.

The Rest of the Body…
Once the heart of the A/C service and repair portion of your shop is addressed, that still leaves the rest of the tools and equipment needed to diagnose and remedy today’s complex air conditioning systems.

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There are three main groupings of tools to review for the coming A/C season. General service tools, which allow for the assembly, adjustment, or removal and installation of components of the system. The next grouping of tools is Inspection Tools. This includes both electronic and ultraviolet leak detection equipment, as well as some measuring tools. The last group of tools is Charging-Refrigerant Handling tools. This group includes any of the tools other than the R/R/R machine that help handle or measure or manage refrigerant. I will address some of the key points of the tools below.

Inspection Tools
This group of tools includes the equipment that you will use first during the diagnosis of a vehicles’ A/C system. It is critical that you identify and verify the refrigerant that is in the system prior to any work being done. There are two issues to worry about as it relates to refrigerant currently. The first issue is quality or purity of the R-134a that is available in the marketplace today. While the price of R-134a has actually come down significantly, there is a rise in blended and contaminated gases on the market. A lot of non-branded or “white box” refrigerant is being bought and installed in vehicles. While a large percentage of this gas is fine, there is a portion of it turning out to be full of non-condensables and moisture, other gases etc.

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The second issue is one of safety for you, the technician. There are still some hydrocarbon-based refrigerants floating around on the market. While this has been declining over the last several years, it is still worth checking before you work on a car. There are choices for refrigerant identification equipment. There are hand-held units that you can carry around with you and check the vehicle before it ever comes into one of your bays. There are also units that are made to permanently attach to your recycling equipment. Both styles are fast and easy to operate. In a matter of a few minutes you will be able to determine what refrigerant is in the vehicle and if it has a large percentage of air. (This is one of the most common problems in poor performing systems!)

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The use of an identifier on every car you work on will save you time, frustration and money.

Leak Detection
Once you have determined the purity and type of refrigerant in the vehicle, you will most likely need to verify the presence or absence of a leak. Ah!…but what is the best type of leak detection equipment? Electronic or ultraviolet? This is an ongoing argument among A/C techs, A/C suppliers and tool distributors. So what is the answer? The answer is BOTH! While both types of leak detection are effective, the reality is that some leaks are so tough to find that you are going to end up using both methods of leak detection to verify the source of the leak.

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Refrigerant Charging and Handling
This group of tools includes one of the most basic and familiar items in your box. The A/C manifold set is possibly the most used (and abused) tool in the box. The manifold is easily damaged by fans, hot manifolds, getting crushed, dropped, banged, etc. The manifold is prone to leaks at hose connections, gauges, couplers and shut-off valves. Take a good look at the manifold set before you get busy this season. A little preventive maintenance will go a long way.

The two other critical items to think about in this category are the vacuum pump and the digital scale. The vacuum pump is one of those items that we tend to ignore and abuse until it fails. We just don’t think that much about it — or the upkeep it needs — until it fails. The key maintenance item that needs to be attended to on the vacuum pump is changing the oil.

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Digital scales have become more important than ever before. As I mentioned above, the newer cars with low capacity systems will not tolerate under- or overcharging. In some cases you may not have access to your A/C machine, and in these cases you may recharge a vehicle using a bulk cylinder and a digital scale with programmable capability. These “set and forget” tools are great.

General Service Tools
This group of tools is a bit of a catch-all for everything else in the arsenal to repair A/C systems. This grouping of tools is the largest number of items in your box. There are more and more vehicle-specific tools required now than ever before. There are special line disconnect tools and specific compressor tool for various brands of compressors. There are hose cutting, bending and crimping tools. There are fittings and adapters of all kinds. There are many special couplers now needed for tight access areas. There are all kinds of clutch removal tools needed to service the newer cars. There are literally hundreds of generic and specialty tools that you may need to service all the different vehicles on the road today.

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Checkup
Taking care of your tool needs for the upcoming A/C season is a little bit like taking care of yourself… If you have had a checkup recently, the doctor probably spent most of his/her time talking to you about your heart and how important it was to take care of it. It’s no different when talking about the tools and equipment for servicing A/C systems. If you take care of the biggest item first, which is your recovery machine, you should be in good shape.

Setting the Course for Change The Improved Mobile Air Conditioning (I-MAC) 30/50 project was established in 2005 by the Society of Automotive Engineers (SAE), the Mobile Air Conditioning Society Worldwide (MACS) and the U.S. Environmental Protection Agency (EPA) in a collaborative effort to reduce vehicle air conditioning fuel consumption by at least 30% and minimize refrigerant emissions by 50%. The project’s fundamental purpose is to cost-effectively design next-generation mobile A/C systems with fewer leak points and improve service procedures to minimize the refrigerant emissions of R-134a. As a result of this partnership, new A/C systems are becoming physically smaller and require increased charge accuracy. Accordingly, the SAE continues to set tighter standards for automotive A/C recovery, recycle and recharge equipment.
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Applying the New Standard In late 2006, substantial progress was made toward reaching these goals when SAE published the new SAE J-2788 standard. Once implemented, it requires all service equipment to be able to recover 95% of the refrigerant and recharge to within 1/2 oz. Without exception, existing refrigerant service equipment will not meet this standard. However, these existing systems are exempt from upgrades under a “grandfather clause.”

Investing in the Future When purchasing new A/C service equipment, look for a machine that meets all the stringent requirements of the new SAE J-2788 standard. One that provides a recharging accuracy to within +/- 1/2 oz. will translate into fewer customer comebacks and more profit for your shop by meeting the stringent specifications of new vehicles. The best charge accuracy that could be claimed by older generation service machines is +/- 1 oz., a 3% error on a 2-lb. system. That same charge accuracy on a 14-oz. system is more than twice the error at 7%. As the shop owner, you will avoid costly comebacks with these new R/R/R machines by ensuring critical charge accuracy and realize more profits per service by recovering more refrigerant and charging less.

Courtesy of Robinair.

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