The Trainer #42: Tips on finding A/C refrigerant leaks

June 1, 2015
The June 2015 edition of The Trainer looks at the use of ultrasound and CO2 for leak detection, as well as offer you tips on using the more conventional methods more successfully.

How many of you remember the days of automotive a/c systems that held three or four pounds of refrigerant? Back then, it was considered“acceptable” to lose half an ounce of refrigerant per year from a single leak source. Move the clock forward to modern times, though, and you’ll discover that today’s systems are not quite so forgiving. There are numerous models now that use less than one pound of refrigerant to fully charge their systems. Even small leaks can quickly impact system performance, resulting in your customer’s return to the shop at the tail end of the season after having it repaired (or se we all thought) at the beginning of the season. And in some parts of thecountry, there is no season! The demand for a functional a/c system is yearround.

Recovery/recycling/recharge (RRR) equipment can be used to check for the presence of a system leak, and on vehicles equipped with R1234yf it is a required step. But the machine can’t tell you WHERE the leak is. To find the exact location, many of us prefer the use of a refrigerant “sniffer” – a device that detects the presence of refrigerant in the air around the a/ccomponents (if a leak is present).

At least, that’s the idea. Older sniffers would trigger on just about anything and a few years back, the SAE issued improved standardsthat helped quite a bit. But if your shop is like any of the ones I’ve worked in during my career, other factors (like the breeze kicked up by shop fans on a hot summer day) limited the effectiveness of this method when hunting elusive leaks.

Dye is another popular method and can be very effective. One of the drawbacks of dye is the amount of time it takes to circulate through the entire system. Another is the danger of overdosing the system – adding dye to one that has already received a few shots of the stuff. A third is being able to see the whole system, especially the evaporator core, a common source ofleaks.

 So what do you do to chase down a stubborn, hard to find leak source?

There are alternatives, and in the June 2015 edition of The Trainer we’ll take a look at the use of ultrasound and CO2 for leak detection as well as offer you some tips on using the more conventional methods more successfully.
Click here to subscribe to the print or digital edition of Motor Age!  
Due to factors beyond the control of Motor Age, it cannot guarantee against unauthorized modifications of this information, or improper use of this information.  Motor Age magazine (Advanstar Automotive Group) assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. Motor Age recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video.  Due to factors beyond the control of Motor Age, no information contained in this video shall create any express or implied warranty or guarantee of any particular result.  Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not Motor Age magazine or its corporate parent, Advanstar.

Check out other videos on the Motor Age YouTube page

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.

Sponsored Recommendations

AIRCAT Solutions - Small Ratchets With Enormous Power

Experience the power of AIRCAT's diverse ratchet selection. Each designed with a unique transmission gear for faster torque buildup and unbeatable performance. Their compact sizes...

Unmatched Power and Comfort: AIRCAT Grinders for Every Workspace

AIRCAT grinders deliver powerful performance with high RPM and efficient, quiet operation. Designed for comfort and control, they feature ergonomic handles, extended reach, and...

What Are the Advantages of Air Tools Over Cordless Tools?

Discover the advantages of air tools over cordless tools.

AIRCAT Tool Reviews: The Nitrocat 1056-XL Compact

Hear what senior autotechs have to say about the AIRCAT Nitrocat 1056-XL compact impact wrench. They’ll provide their reviews on tools they own and have been using every day on...

Voice Your Opinion!

To join the conversation, and become an exclusive member of Vehicle Service Pros, create an account today!