Making Sense of Auto Motive Air Conditioning Gases
Having worked in the Automotive industry, including Mobile Air Conditioning Systems (MACS) for almost 33 years I had found myself frustrated and confused when seeing legislative changes with what appeared to be little qualification given to the working industry. The original environmental effect of R12 Freon on the ozone layer is well known and R12 had to go, there was no question of that and I fully agree with the restraints that were put on R12 including its use, handling and recovery. New South Wales went way further than most Australian states by requiring Technicians to be licensed and educated.
R134a refrigerant was moved in as a replacement but so were Hydrocarbon refrigerants (HC), the later being quickly banned somewhat unfairly largely by questionable bad media reports and scare tactics. I do remember peer discussions questioning the use of a Synthetic Gases as we knew nothing of the long term effects but our hands were tied eventually and R134a was it.
We now know the long term affect of R134a, it is referred to as a Super Greenhouse Gas having conservatively speaking; 1500 times more greenhouse potential (GHP) than CO2 (Carbon dioxide) and other reports indicating up to 3400 times more greenhouse potential, therefore R134a should defiantly be replaced and urgently.
Around the time Australian Refrigeration Council (ARC) was formed, the NSW ban on Hydrocarbon Refrigerants was lifted which brought NSW into line with all the other states, including Victoria who never placed a ban on the use of Hydrocarbon refrigerants. The NT revoked a cautionary notice they had for HC shortly after NSW, but Queensland still has a HC handling licence requirement. Now interestingly over 15 years of Victorian experience has provided long term data involving the use of HC’s in mobile systems.
We again seem to be in hands of the chemical companies but it does appear that hydrocarbons are to be used if we don’t want to completely redesign out air conditioning systems. What appears to be down the track at this time is a new $100 per kg flammable HFC fluorocarbon designated HFO-1234yf, if the chemical companies have their way, a new gas (Remember we were told that R134a was environmentally friendly) but there are also natural products freely available, and have been for some time.
Originally Hydrocarbons were band on reports of projected failure rates, these were quite sophisticated mathematically prepared reports and were the basis of what the authorities needed to make decisions particularly in regards to public safety, but with the long term data now available it is found that those projections were quite inaccurate and to this date there has been no reported in cabin fires, explosions or injury’s associated with the use of Hydrocarbon Refrigerants. This report can be downloaded and studied from here. This report was made by I. L. Maclaine-cross School of Mechanical and Manufacturing Engineering, The University of New South Wales.
This brings me to my personal experimentation. I purchased some Hychill Minus 30 Refrigerant after some lengthy conversations with the people at Hychill and decided it was time to see for myself, I promptly converted my 2000 model Nissan Navara 4WD to work on Minus 30 and was surprised by the results. Firstly the Vehicle only required 200 Grams by weight to recharge the system fully (it turns out this is about the same liquid quantity), but the system seemed to cycle more frequently, actually the compressor spent more time off and secondly it was noticeable that less load was required to turn the compressor, I have a hill that I climb every day on my journey home and always notice the compressor kick in going up the hill, on this occasion the power drop was almost unnoticeable, I actually turned the A/C on and off a few times just to check.
Shortly after this time I had a customer turn up at my business with a very well kept low KM XD Falcon V8 which was still charged (although only just) with R12, He was selling the vehicle and promised to have the air conditioning recharged before he sold it. This was an old system, with the old York Compressor and I really hesitated at the thought of converting the system to run on R134a, My experience was telling me that the system would most likely have a major failure shortly after this conversion and being conscious of the super greenhouse properties of R134a it really was not an option. I discussed my experiments with this customer and honestly felt the Hychill product would be the best option. I actually felt confident that the system would work well. The owner agreed and we decommissioned the R12 system, replaced the filter and fittings and recharged the system with Hychill Refrigerant. The result was nice moderate head pressure, quiet compressor and 4 degrees centigrade out of the vent, the system worked better than I remember those systems ever running; “now I am impressed.”
We made sure that the system was clearly marked by stickers that are provided by Hychill with the bottle of refrigerant and explained clearly to the owner that the refrigerant used was a hydrocarbon and to let the new owner know.
The more I investigated the more support material I found for the use of Hydrocarbon Refrigerants. A report from Greenpeace raised my eyebrow when it was revealed that as an insurance risk factor was somewhat lower. The fact that the system pressures are lower the insurance risk was calculated lower if Hydrocarbons were to be used.
It appears to me that the Exploding Car myth is exactly that “A Myth”. Known facts are that R134a when mixed with lubricating oil and undergoing an explosive decompression (I E. Crash and puncture of a pipe, hose or condenser) is flammable, the refrigerant /oil mixture will ignite. And in all my time working with Mobile Air Conditioning systems I have yet to see a catastrophic failure of an evaporator, under a dash of a car, I have found extremely slow leaks that take weeks or months to render a system inoperable, but if this were a Hydrocarbon system the air fuel ratio would never be high enough to be a flammable mix. The fact that the Hydrocarbon Refrigerants are odorised would mean that leak could be detected by the driver’s nose, alerting them of the leak.
Thinking logically, 200 grams of refrigerant running around your air-conditioning system with 90% of the A/C system under the bonnet separated by quite aptly called the “Firewall” there is little to no chance of any danger at all. If that does scare you, I believe that you would be absolutely terrified about 90 litres of LPG sitting behind your seat in the next Taxi you board. Every time I pass by a Taxi rank I smell LPG, but an air conditioning system is sealed, no leaks, because if it leaked it would not work. Lastly, the evaporator being about 10% of the Air Conditioning system is in the safest part of the car in the passenger compartment, the most protected part of the vehicle in an accident, and if you are worried about that exploding I think the explosion of an Airbag inflating would be more of a concern.
It appears to me that the main opposition for the use of HC refrigerants is coming from a competitive angle protecting the interests of other refrigerant manufactures, with the main push being flammability, Keeping in mind that R134a when mixed with lubricant is also a flammable mix, is there really a difference?. Consider this, when R134a and PAG oil burns the by-product is Toxic and the PAG oil itself is corrosive in the right conditions, the HC refrigerants allow the use of a relatively safe mineral oil.
I contacted one of my major suppliers of air conditioning parts, particularly compressors and asked how they felt about hydrocarbon refrigerants, only to be told that they won’t warrant the parts if HC’s are used. When questioning as to why, the only answer they could provide me with is that HC’s have not been tested and therefore not indorsed. My question is “Why have they not been tested?”
Through my investigations I found a company in Victoria C-A-R (Compressors Automotive Remanufactured) who have been reconditioning Automotive Compressors since the early 1990’s and have had extensive experience with HC Refrigerants, they recommend the use of HC’s and in fact will quadruple their warranty on a compressor if HC refrigerants are used correctly. With further correspondence with this supplier it was relayed to me that the compressor has a much easier life when HC’s are used and can have a much longer service life.
Considering all the Data available indicates that HC refrigerants are as safe as conventional Synthetic options I start to wonder about the legacy we leave our future generations, here we are pumping a super greenhouse gas into our air conditioners a Gas that is made in a laboratory and has significant dollars attached in regards to patients and licensing arrangements to interested parties, then we have a natural alternative, a Refrigerant that is naturally found in the environment, zero ozone depleting, extremely low Greenhouse Potential , an Australian owned resource and being a natural product I believe there is no patients or licensing limiting production, there seems in my mind no problems in choosing which direction we should be heading.
What problems can we face? Well first of all is the possibility of cross contamination of stocks, we don’t want that. At present there are no particular fittings to suite Hydrocarbon refrigerants, so the systems will have to be clearly marked, one idea I have contemplated is a plastic tag with a zip tie to attach to the neck of a charge port. Also there is no restrictions on the use of the Hydrocarbons except for Queensland who have issued handling restrictions, I feel that in order to protect the industry and to keep safety to a maximum only qualified people should be allowed to use these refrigerants, the current level of competency required for R134a should be sufficient as long as practices are followed. Also I feel the use of pressure pack cans that are available to the public to top up systems should be restricted; the possibility of overcharging a system when refilling a system with considerable leaks could be of great concern and could end with injury or worse.
I am trying to remain impartial here but with the more information I uncover the more I start to lean towards the Hydrocarbon Refrigerant. Over the past 15 years we have been blindly pumping R134a into our customer’s vehicles, the last 6 years or so we have been actively recovering and recycling R134a when it was reviled that it is a major contributor to global warming but still I always need to top up my stocks. My records show that up 10 to 15% of R134a seeps out of a sealed system every year, what this means is that eventually most of the R134a I buy and sell to my customers is eventually going to end up in the atmosphere adding to the global warming problem. Remember R134a has 1500 times more Global Warming Potential (GWP) than carbon dioxide (CO2). There are more and more compressor and hose failures which if the pressures were reduced would be significantly lower and removing potentially corrosive lubricants will reduce this even further.
The industry has an option here; we can collectively and purposely choose to make a difference if not just for the environment but also our customers. I have been questioning my customers and in particular the younger generation on the pros and cons of refrigerants and let me tell you, the prospect of being environmentally friendly has a big sell factor, they feel good about doing something positive for the environment and we can give them that. Just think of all that R134a we can remove from our environment if we just started gassing with a HC alternative, Recover recycle and reuse R134a as you can but reduce the amount of new stock that you buy, it will eventually run out and we have accomplished something big for the environment. Not only by reducing the amounts of R134a going to the atmosphere but the carbon footprint of a vehicle requiring less horsepower to operate an A/C system. One or two cars will make little difference but potentially millions of motor vehicles would make a real impact.
Thankfully moves are already underway to stop the use of R134a and from the reports I read 2015 should be the last we see of it, the Government is attempting to reduce the countries carbon footprint and minimize the effects of global warming, here is a way of removing a massive contributor to global warming, we have a natural product with many years of data that does not cause major problems to our environment or we have chemical manufactures synthetically manufacturing chemicals which we will not know are good or bad to our environment for many years.
Just how much damage has been done to our environment already, let’s not be lead by the nose blindly by chemical companies with vested interests, the solution and been around since the 1890’s but we have been told not to look. So I ask you again to please consider the legacy we leave our future generations.
Paul van der Weegen M.I.A.M.E.