A/C Leak Testing Using Compressed Air, Soap and Water (any car)

For those of you worried about using compressed air because of moisture. My question to you is, what do you think is in a system that has a leak and all of the refrigerant is gone? Atmospheric air and moisture! This is a tried and proven test for me over the last 25 years and it is one that everyone can do. Who has a bottle of compressed nitrogen sitting around anyway, especially when you only do a few A/C jobs a year.

Tools used
- A/C Manifold Gauge Set
- Vacuum Pump & Gauge Set Assortment (least expensive kit I could find that I felt was descent and it is the one I use)
- 3.0 CFM Vacuum Pump (same pump that comes in the kits listed above)
- 6 Gallon Air Compressor 150PSI
- Spray Bottle W/Sprayer
Car Wash 64 oz
- R-134a Can Tap Valve
- Bayco NSR-2168B LED Rechargeable Work Light - 600 Lumens w/3 Magnets Lithium-ion Battery

Related videos
- HVAC and Cooling systems troubleshooting and repair
- A/C clutch not engaging - 2005 Honda Odyssey
- A/C Leak Testing and Repair part 1 - 95 Jeep
- - A/C Leak Testing and Repair part 2 - 95 Jeep
- A/C Leak Testing and Repair part 3 - 95 Jeep
- Air Conditioning Not Working (system performance, leak test) - Honda

On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!

Disclaimer:
Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC 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 ScannerDanner LLC, 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 ScannerDanner LLC.

[ScannerDanner]

I NEVER MIXED COMPRESSED AIR WITH THE REFRIGERANT! IT WAS EMPTY FROM A LARGE CONDENSER LEAK!
Some of you want to argue, that what I showed was unsafe. Please tell me how an empty system, filled with compressed air, is a safety concern. I'm not asking about the supposed contamination. I am asking about the safety side of this procedure. I certainly do not endorse unsafe practices.

Here is something I found on a Google search from some engineer forum...

HFC-134a is not flammable in air at temperatures up to
100 deg. C (212 deg. F) at atmospheric pressure. However, mixtures of HFC-134a with high concentrations of air at elevated pressure and/or temperature can become combustible in the presence of an ignition source. HFC-134a can also become combustible in an oxygen enriched environment
(oxygen concentrations greater than that in air). Whether a mixture containing HFC-134a and air, or HFC-134a in an oxygen enriched atmosphere become combustible depends on
the inter-relationship of 1) the temperature 2) the
pressure, and 3) the proportion of oxygen in the mixture. In general, HFC-134a should not be allowed to exist with air above atmospheric pressure or at high temperatures; or in an oxygen enriched environment. For example HFC-134a should NOT be mixed with air under pressure for leak testing or other purposes.

[dandiy]

I had a similar vacuum leak issue on a 2003 Envoy that was dead empty, tried the compressed air at about 70 psi and found the leak in 5 seconds, litteraly hissing out the condenser, no soapy water needed. This weekend will replace the condenser . Great tip and videos as always. Thank You!

Both of your A/C troubleshooting videos using compressed air, with explanations of the various systems, is outstanding Paul!! You have made this complicated system a workable one for us DIYers, and plenty of thanks to your fine son in helping his dad too!!!

[swfloridacarguy]

Paul, I trained on Automotive AC at the GM training center in Tarrytown NY many years ago. Over the years as a Chevrolet Tech I worked on many different systems and always took the advice of the instructors. They had developed many different techniques that weren't in the book and still aren't. Please continue with your advice no matter what the criticisms are...

[MarioMartinez-xlpx]

Man first off just want to say thank you for your content and the information you share. I was able to find the leak on my wife’s 2011 Chevy traverse and replace the parts that needed to be replaced. The local shop wanted an arm and a leg for the work I was able to get done at the fraction of the cost by watching your videos and investing in a set of gauges and a vacuum pump. Thanks to y’all my wife’s SUV is ready for another hot summer in the high desert of CA.

[motazuk]

Most of your tutorials are 100% money makers. I have used your tutorials for research, diagnostics and repairs. All without issues. Got nothing but great appreciation. Thanks man!

[samueladams]

to hear someone speaking clear english while doing a video. Some of these tech videos move so slow relaying pertinent information, that I can't even get through the first thirty seconds of the video. Thanks for an informative production.

[alloutofdonuts]

This is probaly one of the more helpful videos I've come across in my searching for the last week about the proper way to do this.

[gerardlunow]

Great video. Your comments are right on. Most show a simple video they copied for elsewhere and don't really understand it. You actually thought this whole thing through. Smartest video so far. Thank you!!

[damiensmith]

Thanks for this it saved me wasting expensive refrigerant. I put the money I saved towards a small compressor instead. The stethoscope tip from another reviewer will help in hard to reach parts of the system. I cant do any physically demanding work on my car due to poor health. Your video has empowered me to tackle this job myself. I will gain that sense of achievement from doing it myself. Thanks.

[robertpagel]

I will say your videos on ac troubleshooting and repair are the best anywhere. I’ve been quoted $3500 to start on ac fix. With your help I’m under $1000 with rear evaporator core, compressor, r-134, and vacuum pump and manifold gauge. Thank you for videos!

[rss]

Good to see that you actually tracked down the problem... love the use of compressed air instead of nitrogen. quick and dirty.

[foreignerthisworld]

Fantastic video! Thanks for taking the time and effort to make a quality production. Is helping me much in my A/C challenge with my 1996 Suburban!

[kylehasten]

Thank you for this video. Been fighting a leak on a completely new replaced system on my 86 mustang. Wouldn't hold a vaccum so I could add refrigerant. This let me find the leak in the brand new pressure switch. Replace switch, now it holds vacuum.

[robertmattison]

Just found your channel. Great job. Audio excellent, Video really good. Thanks for upload this onto youtube.

[EddieLowXScience]

I was gonna bite the bullet and buy one of those ac leak dye. Now I'm gonna go ahead and pressurise my ac system looking for leaks. Cheers man!

[daveqlockard]

I was ready to take this system I just built to the shop and pay$$$! New compressor, condenser, accumulator, and orings all around. Yet, I couldn't maintain any vacuum. Your simple and straight forward approach - I found my leak. You are an obvious genius~! Thanks...

[wysetech]

It's funny how some people are such experts on Y-Tube. Experience means nothing. Better not undo a fuel line, two drops of fuel might explode into a raging inferno. I have been repairing A/C systems for over 40 years and I have never had a problem with using Nitrogen, compressed air, electronic or refrigerant (R-12 days) while testing for leaks.
In real life repair you do what you have to do within the limits of your knowledge and experience. As far as moisture goes, on the assembly line they pump em down for 10 seconds and then fill them. I guess that's why they install a drier. A tip for soap, Dawn liquid dish washing soap seems to make the most bubbles.
Well done, Paul in my opinion.

[SurvivalInFlames]

These past 2 videos you've posted on ac diag are the absolute best on YouTube. Please keep them coming brother:)

[tomasnewson]

My main job is mobile car AirCon. Over here people are under the impression that car AC systems just need ‘ topping up ‘ every couple of years. As if the refrigerant is a consumable substance...

Anyway, this video is brilliant, and is exactly what I was looking for a couple years ago when starting out. Really thorough and full of facts!

The only thing I do differently is that I use oxygen free nitrogen to pressure test. But can’t see a huge problem with using compressed air as long as the system is thoroughly vac’d afterward.

Bang on mate.