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Part 2: Air Conditioning Sealants, Stop Leaks, Leak Stops, etc. — Do You Use Them Or Not?
by John R. Hess
© 2003 All Rights Reserved
Appeared July/October 2003 in
Cool Profit$ Magazine
As I was finishing this article, yes finishing, I received the latest edition of the MACS magazine, ACtion™. In it is a comprehensive report titled “SAE 2003 Alternate Refrigerant Systems Symposium,” which succinctly updates mobile A/C manufacturers, distributors and service shops worldwide on the status of current and future refrigerants and systems. The part of the piece that seemed most significant to me, however, was when they described, and quantified, the importance of reducing refrigerant leaks in current systems.

Leak prevention methods (but no sealants)
Several methods are mentioned to achieve a “low-loss” leak specification, including new hoses, seals and less leaky compressors. Design options that might be available in the future are: more efficient compressors, more sophisticated computer control of variable-displacement compressors and cabin inlet air, a refrigerant oil separator and a separate heat exchanger just for the suction line. What's a little peculiar is that while there are ads for various sealant products within the magazine, there was no mention whatsoever of any type of A/C system sealer or stop leak in the article. Could it be that they purposely left that subject out knowing that full well that Cool Profit$ would cover it? Hmmm?

Moving on, the point of my story about their story is that “larger” HFC-134a refrigerant leaks are now definitely a worldwide no-no. No matter how cheap refrigerants may get, it’s still going to cost manufacturers real money if their future vehicles leave the factory with an A/C system that passes more gas in a year than a butterfly. Consequently, I added this section to, and in front of, the original article. Please read on.

Leak rates identified
According to the ACtion article, a study by the European Commission showed that the average vehicular leak rate was 51.8 grams/year (1.8 ounces/year), with a high leak rate of 70 (2.5 oz/yr). Plus, the Europeans found that vehicles in their first year of life tended to leak more than those in years two or three. As a comparison, studies in North America show rates of 15 to 30 g/yr (.5 to 1.1 oz/yr).

We’ve all known that because of it's for global warming potential, the European Community has targeted R-134a for elimination as a mobile refrigerant. What’s new is that a system of quotas, penalties and credits is being developed to hasten both leak reduction and the introduction of suitable replacement refrigerants and systems. But even before those take effect, starting on 01/01/05, vehicles sold in Europe using R-134a will have to prove that their systems will not leak more than 40 g/yr (1.4 oz/yr) for a single evaporator system, and 50 g/yr (1.8 oz/yr) with dual evaporators.

While covering ways of improving present R-134a systems, the article mentions that a quick and low cost method of reducing the amount of this refrigerant in the atmosphere is to just reduce system leakage. In fact, such “enhanced” future systems in the US may end up using the same proposed leakage standard as the Europeans: 20 g/yr (.7 oz/yr) for a single evaporator, 25 g/yr (.9 oz/yr) for the dual unit.

The ACtion article also nicely details the progress of alternative A/C systems that are moving through the development process. While none of these are necessarily new to refrigeration, not until now have they been seriously considered as potential replacements for vehicular passenger compartment cooling systems: Secondary Loop, HFC-152a and Carbon Dioxide (CO2). However, though all have prototypes in the field, because of individual downsides or glitches that remain to be worked out, or proven safe, none will be showing up in you bay any year soon. Face it, 90% of your A/C business for at least the next 10 years will use R-134a. For those who have dropped R-12 altogether, HFC-134a will be 100%.

What you’ve just read clearly adds significance to the subject of sealing refrigerant systems, and sealing them by any means possible. Whether you like them, and use them, or not, at least be aware of what they are, who’s using them, their successes and their failures. Now, here’s the original article. (Note: If you use or have used a sealant, please fill out the survey form on page 22.)

No sooner had the last issue of Cool Profit$ Magazine hit the street when I got a telephone complaint from a shop owner in Arizona; he was somewhat shocked and offended at the full-page A/C system sealer advertisement on the inside front cover. After some discussion, it turns out that he had just confirmed his first actual sealer-contaminated system by use of the Neutronics detector. His first gripe: being forced to now spend extra labor in running this new diagnosis for each unfamiliar vehicle that drives up.

Gripe #2: finding sealer in the system and not wanting to contaminate his recovery equipment caused him to send the customer down the street; therefore a no-revenue job.

Gripe #3: besides losing the revenue, the shop owner also felt guilty thinking that the next service tech, or the vehicle owner himself, would just release that refrigerant into the air. Or, if the vehicle owner doesn’t tell him, the next tech might not be equipped with an identifier and do damage to his recycling machine as he sucks in the gas. I found those concerns legitimate and decided to research the issue.

Two years ago, I put off a Part 2 to my Part 1 A/C System Sealer article of April, 2001. Part 2 was supposed to focus on shop experiences. I did so because of the lack of practical experience that most of the new distributors had with the product; many of who had only been using it for a month or so. As they say, that was then, this is now.

Not intended as quick fixes
All of the vendors of sealant, sealer, stop-leak, etc., that I contacted admitted up front that while do-it-yourselfers were getting and using the product, it really belongs only in the hands of a professional A/C technician. Techs can be expected to use it only after ensuring that the intended system is first “qualified” for a sealer (via various test methods), and then that it’s clean and dry (dry being the key word). The Hole Sealer's sealing material is actuated by either air or water. Clearly, you don't want to dump it into an A/C system containing any amount of moisture.

Many of the horror stories associated with A/C sealants are caused by do-it-yourselfers jamming in a desperation load, and then, deciding that more is better, giving the system an insurance shot or two. Of course, without a pump they could not have evacuated the system. And, since a new accumulator costs money and requires installation (with funny fittings), well, forget that.

Most professionals consider a sealer to be a product of last resort (either the leak cannot be found, or like in some evaporators, the location is known but the cost of an R & R is beyond the customer's means). There are technicians, however, choosing to add sealant to every job, as a dose of insurance. One of these is Steve Mavromatis, owner of East York Auto Electric and A/C, East York, Ontario Canada. Steve, who will NOT use the product for a repair, has been using Cliplight SuperSeal for over three years, and has at least 1000 installations on the road. Since he started using the sealant, his comeback rate has dropped by 99%. This includes those annoying six month to year-old leaks where the customer straggles in at the start of the next season. (Steve GUARANTEES his work.)

Steve’s installation requirements: the system must first be made to be leak-free and the drier must be replaced. Even though he's not a hundred percent sure that it was the sealer’s fault, since having a couple of unexplained fouling problems using sealers in X-block expansion valve systems, he avoids using it in them. A suggestion: Steve always converts GM single-lip compressor seals to double-lip. With the compressor on the bench, he's got the labor down to a half hour. As with sealants, this changeover also seems to be paying off.

John Keilly, of Keilly's Automotive, Bradenton, FL has been using the Keep-It-Kool sealant for over a year and has yet to find a “small” leak that can't be fixed. A small leak is where the system will still hold a 29” vacuum for at least 45 minutes. For evaporator leaks on a Chrysler minivan, without hesitation he now gives the customer a quote for both the full R & R with evaporator replacement, and, the sealer option. As such, what he’s now experiencing is that the customers no longer walk; they’re happy, he’s happy.

John has no problems with X-block systems, like those on a Jeep Cherokee. They seal up fine. What he knows it won't seal are high-pressure switches and cutout valves.

Hal Gruber, owner of Rose City Auto Radiator, offers both radiator and A/C service, and distributes a full line of radiators and air conditioning parts. He’s been very pleased with the Keep-It-Kool System Sealer, having heard early complaints of orifice tube and drier fouling with other products. What convinced him that the sealer worked was when he used it in his own ‘93 Plymouth Voyager. Using a “sniffer,” he knew it had an evaporator leak. Within a few minutes of adding the sealant, the leak checker became quiet. The system still worked three years later when he sold the van. He uses the product regularly on Jeep Grand Cherokees, 850 Volvos and Audi A4s.

If a vehicle leaks its charge within two or three days, Hal disqualifies it as a sealant candidate. As an absolute last resort and hoping for miracle, he once tried it on an ‘87 Lincoln with a rotted case; no luck. In any case, Hal continues to use it, his wholesale customers continue to use it, and he gets no complaints about the product.

Tony, of Toronto Canada’s Royal Radiator, installs a sealant in every big A/C job—as insurance, not a repair. (Big, in this case, means $1500 or more.) As with Steve above, it’s virtually eliminated the annoying comeback leaks that plague even the best of shops, and annoy the customer as well. The customers are paying for the product, which he tells them is an A/C system conditioner. Of course, the product he’s using also contains “system conditioners.”

Tom, of Ohio’s Parma Heights’ Rad Air, did not have good luck with the sealers they used a couple of years back. They found sludge and contamination which was attributed to the sealers they had installed. They have discontinued using any sealants.

Bruce Balfour, of Bellflower, California’s Mac’s Radiator and A/C Service, had similar experiences as Tom at Rad Air. They used the product early on (two or three years ago) and it did stop some leaks. However, they also had a couple jobs come back, the cause of which seemed to be fouled driers. Bruce also discontinued using sealers.

We did receive one anonymous report where the writer was adamantly opposed to sealants. However, we will not include any opinions or data within our articles, either PRO or CON on any subject, unless we know the source. On request, we will gladly hold the submitter’s identity confidential. If you prefer, you can always communicate directly with our leakmeister, Mole Snoopster (like Robert Novak, he’ll never tell!).

On the same form as above, Bruce Edwards from Atwater Radiator & Muffler, Atwater, CA, signed his name and described his success using SSR International’s Cryo Seal on a ‘95 Ford T-Bird. It suffered from a 3 month slow-leaking evaporator, a 12-hour removal and replacement job of which neither Bruce nor his customer were willing to undertake (work or money-wise). It took him about an hour to install the sealer. That was over two summers ago, and the local car is still blowing cold air.

Since then, and still only for labor intensive jobs, Bruce has installed Cryo Chem in several more vehicles; all of which have been successfully sealed. However, Bruce has noticed a very slight “crusty buildup” around the installation fitting. That concerned him enough so that he now uses a dedicated set of hoses just for installing the sealer. Plus, knowing that any “strange” vehicle coming in for service may have sealant in the system, he’s seriously considering getting one of the refrigerant recovery filters that he has heard are coming on the market. (See listing for AirSept Inc. and ad for “Recycle Guard”)

Terry Jordan, Access Automotive, Napanee, Ontario Canada, got back about four out of ten vehicles he treated with A/C stop leak about three years ago. However, at the time, he was unaware that the driers needed to be changed. Since then, he’s switched to R-416 and feels that this mixed gas is far less prone to leaking that R-134a. Consequently, he no longer uses a sealant.

Seal the evaporator, sell the compressor
Prof. Tom Brown, Centennial College, Climate Control Dept., Toronto, Ont., Canada. (Prof. Brown owns Dealereman, wholesalers of remanufactured compressors, and is the founder of AC Canada and technical air conditioning advisor to Spectra Premium Industries.)
“Since the introduction of sealers four years ago, we noticed a drop in evaporator sales, but an increase in compressor sales, especially for older vehicles.

I attribute that to the fact that a sealer makes an ac job affordable when there is a leaky evaporator and compressor. Since the sealers do a good job on evaporator leaks, but won't seal a compressor shaft seal, customers will authorize a replacement compressor and a sealant.

In my examination of over 2,000 returned compressors over the last three years, I have not noticed a significant problem with sealants. In fact, less than ten units showed congealed sealant. In only a few cases could the congealed sealant be determined to be the cause of failure. This was no doubt, due to the technician failing to replace the dryer and leaving moisture in the system.

In fact, I sold over 460 compressors this summer and did not receive even a single return due to sealers.”

Here’s some A/C sealer comments from persons choosing to go incognito.
European A/C parts and equipment distributor: I began importing A/C recycling machines into Europe in 1991. When I first heard of A/C sealers, I was extremely skeptical about their viability. I’m still not happy about putting a foreign substance in the system, but I can tell you now that virtually every Volvo dealer service department in Sweden keeps an inventory of this product hidden somewhere on their premises. Hidden because it is not officially recognized by Volvo. However, everyone knows that Volvo 850 evaporators last only two years before beginning to leak. A/C stop leak has extended that life significantly. In addition, the product is being used in all the more expensive vehicles throughout Europe. Fortunately, we do not have the do-it-yourself problem here, at least in Northern Europe, as only professionals are allowed to work on A/C systems.

Refrigerant Recovery/Recycling equipment manufacturer: We first started getting a couple of calls in 2001 about our machines being plugged by some foreign substance. The material was getting into the cylinders. During the summer of 2002, the calls increased significantly. In 2003, we’ve been slammed with problem calls. A high percentage of our machines were suffering fouled solenoid valves.

Automotive training manager for a major US chain of automotive parts and service locations: Our corporate policy does not endorse the use of A/C sealants. However, we’ve used, and still use, the Cliplight product successfully in several of our facilities. I absolutely see the place for this product in professional A/C repair; primarily where the labor charge to find and stop the leak is well beyond the means of the vehicle owner. Of course, the system needs to be qualified; not all leaks can be stopped by sealant.

Uh oh, what about violating the warranties?
Understandably, none of the major manufacturers of original equipment parts or A/C equipment wants you to use any of these products. Finding sealant in a failed part can nullify the warranty. Here’s what some of them say about A/C sealants.

GM Bulletin No.: 03-01-38-001: March, 2003. “GM Service Operations DOES NOT endorse or approve the use of any aftermarket A/C system sealer, A/C stop-leak product or A/C seal conditioning product in any GM vehicle. The use of these aftermarket products may cause damage to A/C systems and to A/C service equipment.

A/C system found to be contaminated with A/C system sealers, A/C stop-leak products, or seal conditioners are not covered by GM New Vehicle Warranty or the GM Replacement part Warranty.”

NAPA Temp: “NAPA Temp’s policy regarding the use of these products (A/C System Sealers) is that we DO NOT endorse its use and will deny all claims made against defective products returned for credit that are found to have been exposed to or suspected of containing said sealers.”

Delphi Product & Service Solutions: “Although pure leak detection dyes are permissible, Delphi does not approve the use of any type of air conditioning system sealants. The use of any sealant immediately voids all warranties of compressors. If it is determined that the compressor has failed due to the presence or evidence of any sealant, appropriate account adjustments will be made. Only Delphi compressors with an orange aftermarket label will be eligible for warranty.”

Visteon: “Visteon Automotive does not endorse or approve the use of any aftermarket A/C refrigerant system sealer. The use of such aftermarket refrigerant sealers show evidence of damaging A/C refrigerant recovery/evacuation/recharging equipment, as well as possible damage to A/C refrigerant system components.

Vehicles found or suspected of having an A/C refrigerant sealer in the system should be serviced as a refrigerant system containing a contaminate. Visteon approved refrigerant system flushing equipment/agents may not remove the refrigerant system sealer from a contaminated system, and replacement of the entire A/C refrigerant system is recommended.

Vehicle A/C refrigerant systems determined to be contaminated with an aftermarket refrigerant sealer may affect A/C refrigerant system components warranty.”

RTI Technologies: “RTI recovery/recycling machines are not designed to recover and recycle refrigerant system sealers. The RTI Technologies Warranty may be considered void if evidence of any refrigerant system sealer is found in any of the internal components of an RTI recovery/recycling machine. The owner of a contaminated machine may be advised the warranty is void and all charges for repair will be his responsibility.”

Mazda: “Do not use any aftermarket A/C refrigerant system sealer in the repair of Mazda vehicles. The use of such aftermarket refrigerant sealers may result in damage to A/C refrigerant recovery/evacuation/recharging equipment and/or A/C system components. A system found with or suspected of having an A/C refrigerant sealer in the system should be serviced as a refrigerant system containing a contaminant. Refrigerant system flushing equipment and agents may not remove the refrigerant system sealer from a contaminated system, and replacement of the entire A/C refrigerant system is recommended. These repairs will not be covered under the manufacturer's basic warranty.”

Who are the vendors?
The companies below are major vendors of A/C sealants, sealers, stop leaks, conditioners, etc. Some of them sell both types of sealers, some just one and some of the products contain both types of materials.

1. Cliplight Manufacturing Company
961 Alness Street
Toronto, ON Canada M3J 2J1
800-526-7096, 416-736-9036
Fax: 416-736-9138
E-Mail: arennert@cliplight.com
Web: www.cliplight.com
Sealer Product: Super Seal Premium

2. Keep-It-Kool
PO Box 32, Station U
Toronto, ON CANADA M8Z 5M4 
800-538-6057, 905-542-8279 
Fax: 905-812-1172 
E-Mail: info@keep-it-kool.com
Web: www.keep-it-cool.com
Sealer Product: A/C System Sealer

3. Supercool TSI 
932 South Dixie Highway 
Lake Worth, Florida 33460
800-541-1068, 561-582-2245
Fax: 800-933-4436, 561-582-1499
Web: www.supercool.ac
Sealer Product: A/C Seal Leak Stop

4. Technical Chemical Company
3327 Pipeline Rd
Cleburne, TX 76031
800-527-0885, 817-645-6088
E-Mail: tccmail@technicalchemical.com
Web: www.technicalchemical.com
Sealer Product: Castrol Leak Stop

5. Thermofluid Technologies
2413 E Broadway Ave
Maryville, TN 37804-2758
888-676-9380, 865-983-1633
Fax: 865-983-0068
E-Mail: info@redtekproducts.com
Web: www.redtekproducts.com
Sealer Product: RED TEK® ProSeal™

6. UView Ultraviolet Systems, Inc.
1324 Blundell Road
Mississauga, Ontario Canada L4Y 1M5
877-776-8486, 905-615-8620
FAX: 905-615-9745
E-Mail: sales@uview.com
Web: www.uview.com
Sealer Product: A/C Stop Leak Plus

Sealant detector and removal tools
Neutronics Inc.
456 Creamery Way
Exton, PA 19341
800.378.2287, 610.524.8800
Fax: 610.524.8807
E-mail: Peter.Coll@NeutronicsInc.com

Sealant Detector: QuickDetect™ quickly lets you know if an A/C system sealant has been added to the A/C system.
AirSept Inc., 1155 Allgood Rd, Ste 6
Marietta, GA 30062
800.999.1051, 770.321.4826
Fax: 770.973.3892
E-Mail: info@airsept.com
Web Site: www.airsept.com
Sealant Separator: Recycle Guard filters out A/C sealant, dye and lubricant.

The A/C technicians reading this article are probably in one of three groups: 1) those who may have, or have not, tried system sealers, but will not generally use sealants as a part of their A/C service, 2) those who do, and/or will, use sealants, often or seldom, and 3) those who have never yet, but would like to know more about their usage before making a decision.

This article was not intended to change the minds of those in either group one or two, but rather to help those in group three make their decision. I tried to present both (all?) sides as fair and balanced (sorry, FOX News, but don’t sue) as possible. If there’s more information you need, and you believe that I can get it, please let me know.

If there are ANY factual errors within this article, please advise; they’ll be corrected in the next edition. (Of course, you can question my judgement as well.)
Manufacturers: How does your product work?

If you’d like to explain the details of how your product works, like the nuances of activation and the differences between contact with air or moisture, please present them in writing (as concise as possible) by November 15th.

Next issue: more shop input!
Technicians, it’s again your turn to speak. If you have actually used system sealers in your shop, and would like to share what you’ve learned about them, please fill out the form that follows. What types of A/C system leaks, from what types, years and models of vehicles, have you found to be sealable or unsealable? Are there special installation or usage techniques that you’ve found helpful? How do you qualify-disqualify a vehicle for sealant usage? Let us know as soon as possible.

Editor: Soon you will be able to check in with “current” radiator and a/c industry vendors on the web at: www.imcool.com/buyersguide/.
Vendors: If you would like to be listed as a vendor to the automotive (and Heavy Duty) radiator and A/C service industry, please call, fax, email or fill out the form on the imcool.com web site. Look for Buyer’s Guide Data Entry Form.
Your cost to be listed on the web site and in the 2002 Annual Guide is only $15. For that, you also get a subscription to Cool Profit$ Magazine. In addition, your web listing will be maintained for free (name, contact, address, phone, email, URL, etc.).
One heck of a deal.

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