MACS or Automotive AC

[jg/oz]

Friends, would there be any interest in a general discussion on MACs and future use of MACs in the world and the ongoing pollution of F gasses from
this equipment. As far as I can see Europe is in for a totally new development in MACs and looking into the Non use of HFC in these application as of 2009/2013.
Interesting the EU is voting on the 31/3/2004 (today) what the future will be for MACS worldwide.
Let me know what you think and will start a hefty discussion.
jg/oz

[baker]

I am interested in this subject, but it is one where emotion and economic convenience come first, and practical and scientific considerations come last, unfortunately.

It is fair enough to argue whether cricket or baseball is better, since there is no science involved, but it appears impossible to have a rational discussion about hydrocarbons in refrigeration.

At least in Australia we normally have the option of comparing European and US trends, and choosing the best. Our brief flirtation with R407C before quickly changing to R410A is just an example of the changes that we will soon undergo. We live in interesting times.

[Karl Hofmann]

If the car manufacturers could make a system that could hold in the refrigerant for the expected life of the car, then there would be no need to discuss this, but they can't....Or wont. In the UK, I would expect to change a corroded condenser every three to four years on the same Ford Mondeo (Contour) releasind 750g of R134a the alloy condenser is supported on a mild steel bracket and has a piece of foam rubber jammed in to hold water to ensure the condenser is always damp. Things dont get much better if you buy a BMW or a Merc either, so I would say if the system is going to leak, the let it leak a harmless refrigerant. LOL If you have an engine fire at least when the condenser or pipes melt the CO2 will help extinguish the fire.

HCs are fine in sealed refrigeration, but not under the bonnet

[Peter Croxall]

Hi Karl
I’m just playing devil’s advocate here, but,

If HC refrigerants were used in auto A/C’s, they would not only be environmentally friendly, they would also be quite efficient. As for them being flammable, well the engine compartment is a potential bomb as it is and some cars use propane as a fuel anyway.
As you rightly pointed out, it is the poor choice of fittings and pipework that is the problem. (i.e. NO LEAKS, NO PROBLEM) It is just a thought, maybe it would be possible to locate the fittings most likely to leak below the engine or behind the bulkhead. The only pipes in the engine compartment would be connected to the compressor and these could be made from stainless steel. (High cost though, but very strong). What do you think ???

[chemi-cool]

doing car AC for some years and still do on occaisions - only in summer, I would like to enlight a few aspects,

first, it was and still is one of the biggest problems - pipes.
rubber lasts the longer but the connections leak, aluminium pipes, braeke in time from the vibrations. SS pipes and copper, imposible, SS will crack and break, copper will harden from vibrations and break.
aluminium has no "memory", the best metal pipe.

second, flammability, since we seat on a tank full of petrol, I dont see any special risks with the AC unit, the hot water in the rediator are more dangerous. nut mention moving parts.

car AC installers have a big problem. no one in car production line think of where to run the pipes so some times in order to connect yuor gages, you burn your hand if not loose a piece on the fan ( sounds familiar karl?).
some times its real comfortable to deal with them.

compressor can be under or above or its hard to find its location.
no standards what so ever.I just hope for cars AC techs, that one day the manufacturers will be forced to work under the supervision of international standard

in a country like israel where every car should be equiped with AC by law, its a must.


chemi

[Peter_1]

Friends, would there be any interest in a general discussion on MACs and future use of MACs in the world and the ongoing pollution of F gasses from
this equipment. As far as I can see Europe is in for a totally new development in MACs and looking into the Non use of HFC in these application as of 2009/2013.
Interesting the EU is voting on the 31/3/2004 (today) what the future will be for MACS worldwide.
Let me know what you think and will start a hefty discussion.
jg/oz

Before I can vote, what is MAC?

[chemi-cool]

Mobile Air Condition



chemi

[baker]

I have read that with the shift to 42V electrical systems for cars, the vehicle makers could go for an electrically driven hermetic compressor. There is talk of a combined starter motor / alternator on the ring gear, with more accessories electrically driven - e.g. power steering, water pump, a/c compressor.

[jg/oz]

Friend,
To bring you in the picture MAC or MVAC or BigMac stands nowadays for motor-vehicle AC systems. These systems are at present the biggest CFC and HFC
polluters worldwide and the EU Government is doing something about it.

On 31/3 last (yesterday) the first reading in EU Parliament was to vote for new HFC
laws in MACs as being only allowed after 2011 ( in the whole of Europe for new cars).
By then all probably ( due to Global Warming) every car will be factory supplied with a
MAC system.

The Parliament in first reading also deceided to allow only working fluids (refrigerants)
with A GWP ( Global Warming Potential--HFC 134a is 1300) of 50 or less which narrows
the available fluids to CO2 or HCs or if 'Chemicalia" comes up with something better
a Low GW HFC, USA thought that R152a would be usable (GWP 130) but as you can see not acceptable at present but you never know what might happen with "Chemicalia's" power.

Any-way R152a is also flammble so the step from R152a to HCs ( GWP 3) is very small.

In Australia ( where I live) we have used approx 80 Ton of HCs so far in Macs since 1995 and have 350.000 cars on the road ( with a bank )-( refrigerant in the MAC systems) of 60 Ton. No accidents reported and these are non retrofitted Macs
a straight drop in of a HC mix 60/40 ( propane/iso-butane) or Care 30.

hope this helps

jg/oz

[DaBit]

Personally I like the transcritical CO2 system. The gas cooler can run at much higher temperatures than the average condenser, which can help bringing coolant temperature to nominal levels quicker. Also, CO2 is cheap and safe.

The refrigeration system itself is different from 'classic' systems, but not more complex.

Also, when going to mass production, I doubt that these systems are more expensive than the classic ones.

If CO2 is not an option: HC's instead. They are cheap and good. Flammable? Come on, a car consists of metal and flammable goods (oil, petrol, LPG, plastics, etc.). Who cares about another 300g of HC's if there is 40kg worth of fuel in the car?

Also, to start a fire there must be fuel, oxidizer and ignition. If the HC AC system breaks, the refrigerant is likely to leak out very slow or very fast. In both cases we do not get a LEL < concentration < UEL concentration. And even if the concentration gets >LEL and <UEL, we still need an ignition source. Which is likely not there during the time of the leakage.

[Karl Hofmann]

Although the principles of MVAC are the same are identical to domestic ac or refrigeration, there are considerable differences in the execution of these principles.

I must also point out that the vessels that contain petrol and oils are so designed to contain these substances, fuel tanks are subjected to exhaustive crush and impact testing. On impact the inertia switch will shut down the fuel pump, fuel lines do not enter the passenger compartment.

I agree with jg/oz that motor vehicle ac systems are a massive contribution to the release of refrigerants and should be adressed. As I have said before the reason that they contribute so much to this release is that they are designed to leak. Although alloy pipes are fine for Chemi in a land where rain is rare, it is a curse here in the land of the road gritter and fixing alloy components with steel clips is a boob that even a schoolboy shouldn't make.

Given that MVAC systems have more holes in them than a well known brand of tea bag, I would ask who in their right mind would suggest that it would be a good idea to put in a flamable refrigerant. I have seen evaporators dump all of their charge out through the vents on both Volvos and RangeRovers whilst on test, consider the implications if you were lighting a ciggy just as that happened. Even small evaporator leaks could cause a build up in an heater box, just waiting for an stray spark from a blower motor. Before charging a system, I always test with OFN, how many other MVAC guys do likewise, most of them simply charge the system and say "If it doesn't stay in bring it back and I'll have another look" This car could well be then parked in a closed garage, perhaps with a pit where the vapours could collect. R134a would be bad enough, but an HC?

Condensers are my bread and butter and are so thin and weak that it is not uncommon for ford condensers to bow and touch the radiator under the force of air when the car is at speed, the condenser is also the first major component to be damaged in a front end shunt, this can be a parking ding, again anothe uncontrolled release of flamable vapours with HC's

OK much of what I say could be dismissed as a lot of what ifs, but lets put it this way. All of us on this board are intelligent enough to safely work on our own heating boiler, even if we dont have a card to say so. So I would ask if you lived in a block of flats, would you trust the guy who lives below you to repair his?

[jg/oz]

Friend,
We all have the perception set up by "Chemicalia" that HCs in refrigeration or AC are dangerous while on the otherhand we now have approx 100 million fridges and freezers in the EU with the stuff in it. (HC Iso-butane). So far
no accidents with people who have had no training in how to use these appliances. Same applies for MACs with HCs Riskassessments tell us that deadly accidents with HCs are impossible.The charge is approx 1/3 of the HFC charge due to density differences. It's more riskfull to attend traffic than it is
to use HCs in your system. There are approx 350 million cars now which could be easely retro-fitted to a totally neutral fluid ( GWP 3) and work basically better in performance (also tested) , highly dangerous oils (like PAGs) could be avoided and the world GW Problem for MACs was solved. Unfortunately
" Chemicalia" will than miss out on a multibillion dollar profit Industry and that will be fought vigirously in the future.

WE are at interesting times --HCs have been used and are good, cost is extremely Low and venting in air is No problem.

Just see the relevant inconsistencies in HCs, if you go to a petrol station with eg 20 browsers all in function, it could be possible (and legal) to fill an LPG cylinder at approx 8 m from the browser by opening an orifice in the LPG
bottle of 1.63 mm and blow out LPG gas continiously till it starts spitting
LPG droplets. Nobody sees this as dangerous , it's legal.

I advocate HCs because they are cheap, environmentally friendly, and you need people with a bit of brains to be able to use them.( I do not make nor am employed by the LPG Industry- simply retired)

By the way in the US approx 600 Ton of HCs are used each year and mainly
used by DIY ( Do it yourselvers) to fill up their AC systems. ????

jg/oz

Have a look at:

http://www.euractiv.com/cgi-bin/cgin...1507479&-tt=EN

[chemi-cool]

hi karl,

well, I agree with what you say except that we had 4 inches of rain this winter wet year.

I can add that manufacturers are considering weight as major issue on cars and thats why pipes are so thin.

mind you, on agrcaltural machinery its the opposite. heavy pipes and regular condensers so much less problems.

the problem you have with alloy is the salt on the roads and if you look closely on the rosds in UK, you will notice that there are big spaces between the stones on the top layer, it causes vibrations to the cars systems.

i've noticed it the first time I was drivind on your roads ( maybe cause I was on the wrong side )

but no, I would not like like to drive a car, light a cigarrette and fly through the sunroof.

chemi

[Karl Hofmann]

JG The point that I am trying to make is that domestic refrigeration is sealed, automotive ac leaks like a seive. It is unusual for a fridge to be touched by anyone other than a professional, automotive is fair game for anyone with a rubber pipe and a gas bottle. As I stated to you on the aircondition.com board I am not a great fan of breathing R134a either (It kills Californians) but replacing it with HCs would only be another "Quick fix" I think that CO2 has a brighter future.

If anyone has any HC's I would be delighted to put it to very good use in my brand new gas BBQ

[Karl Hofmann]

Chemi,

I think that the issue of fractured pipes could be adressed better by clipping the pipes up. I've never seen a fractured brake pipe or fuel pipe.

Weight saving?....Hmmm. I still think it is an exercise in making things cheap and nasty so that the manufacturers can make good money on spares and service, not that I should complain

[baker]

Two things.

I believe that the Toyota Prius uses an electric compressor for A/C. Does anyone have any more details?

Can someone please give a brief description of how a CO2 MACS system works. Obviously it cannot be normal with the CO2 critical temp being 31C.

[DaBit]

When CO2 systems arrive, the weakness problem should be solved since the pressures in a CO2 MACS are very high.

How does such a system work? Well, first the CO2 is compressed to a very high pressure of 100-150 bar. The hot, compressed gas passes a 'gas cooler', which is the transcritical system analogue of a condenser. The gas is desuperheated there, and possibly condensed. Then , the gas is passed through a suction gas heat exchanger. Due to the additional cooling, the CO2 condenses. Then, the CO2 is throttled into the evaporator as usual, where it evaporates. And the circle is round.

Pressures are high. Evaporator pressures of 35 bar (500psi) and discharge pressures of 150 bar (2200 psi) are no exception.

[Karl Hofmann]

CO2 systems


http://www.all4engineers.com/preview...lng=en&id=2064

Thanks to jg/oz for finding this one.

[jg/oz]

Friends,
Interesting to read your comments. Also interesting to know is, that after 31/3/ 2004 when the EU parliament voted ( first reading) that GWP in the new legislation refrigerant/fluids, to be used in MACS need to be lower than GWP 50. (R134a is 1300)

Unfortunately a new Conference is held in a fortnight in Washington DC USA, called the Earth Technologies Forum ( yearly held forum) and connected to it is a Mobile Airconditioning Summit. This is held in a forthnight.

Most papers to be represented are based on a new technology with AC fluid
R152a ( GWP 130). Just wander what will be happening there.

Also our head of the Australian Greenhouse Office was supposed to do a
speach/paper on the "Australian experiance with Hydrocarbon retrofit to
CFC-12 Macs". Unfortunately also this paper seems to be cancelled.

You can have a look at the site at:

http://www.earthforum.com (look into the program )

Will keep you informed.

jg/oz

[jg/oz]

Friends,
For those interested in MACS and what is to come in Europe and the rest of the world when low Global Warming fluids are used after 2011 is following.

Australia has approx 20 million inhabitants and our Refrigeration/AC/Macs
workforce consists of approx 25.000 persons. Of the 25.000 approx 50% is related to MACs service and therefore there is good money to be made in this working field.The biggest polluters of emissions are Cars and their MAC system.

The EU is now working on an emission rate of 140 gram/CO2 emissions per
1 km driven which works out on approx 16 km per liter of petrol, to be changed by 2013 ( I think) to 120 gram CO2/km of nearly 20 km per 1 liter of petrol, so cars have to become very efficient.

With the recent leakage of refrigerant fluid out of MAC systems (approx 67 gram HFC per year in the first 7 lifespan years of the car) the CO2 production of the emissions are becoming now ( with approx 240 gram CO2/km emission from petrol ).very high compared to the petrol use.

So at present the influence of the HFC emission are starting to become approx 10/15% of the petrol emissions. Just image what the emission rate of HFC will be if no drastic measures are taken.

So low global warming fluids are the answer be it CO2 of HC or any other low global warming fluid. The Germans are experimenting now with what they call
R723 which is 60 % NH3 ammonia and 40% dimethyl-ether, seems to be able to run through copper tubing and is extremely low global warming.

Have a look at : http://www.bitzer.de/_doc/a/a-501-12.pdf http://www.bitzer.de/_doc/a/a-501-12.pdf

[chemi-cool]

looks very interesting,
now, what will happened to all those "new" systems running on R134a.
are we going to do the same as with R12? will we be again the lab rabbits?

the problem is with all hese organizations that I dont thik they know what they want. the target is very clear - zero ODP. fine with me but I would have expect from them to come with a proven plan.

at the end of the day, we pay for all those games from our own pocket, and if money wasnt the main factor. I want the people I vote for every 4 years to do their job!

any one got a horse for sale? (no AC needed)

chemi

[Bones]

sorry chemi, my boss just sold his charff burner... the only thing it won was its barrier trial!

[baker]

I predict that my 2011 all cars will have 42V high wattage electrics and that all the devices presently driven by the fan belt will be electrically powered. If you are going to engineer your MACS system to use a hermitically sealed compressor, why wouldn't you also make the change to CO2?

We live in times where the "Green" vote is powerful. Unfortunately, "Green" thinking is not always in the best interests of the environment. Just witness the contortions that Germany is going through at the moment with wind power. We live in a time where the best engineering solutions are overridden by what trendy greens want.

CO2 systems may not be the cheapest or the best MACS solution, but it will be the easiest to sell. HC systems could be the best, but too much mud has been thrown.

[Karl Hofmann]

I agree with your prediction. Renault trucks already have an early 42v System, the flywheel is both the alternator and starter, which provides both starting and extra torque when pulling away and on hills, this thing is stall proof. 12 months ago I recieved a Valeo newsletter advertising 42v flywheels and battery packs, the intention is to have several smaller batteries stowed in several locations to make better use of dead space. A few years ago I was told of a number of prototype Renault Clio 1000cc cars with 42v systems, the power and economy that they obtained from operating the inlet and outlet valves via solenoid rather than camshaft was quite fantastic. The amount of work that is being done on the humble combustion engine to drag it out of the dark ages is considerable and I would say that the next generation of engine/car will be quite a leap forward.

Daft green issues keep many engineers in work.

[chemi-cool]

I would like to add some stuff I've fownd on the web regarding 42V.

http://www.valeo.com/pdf/iaa_news/ricardo_uk.pdf

http://www.findarticles.com/cf_dls/m.../article.jhtml

http://www.tierone.com/42voltrr.html

this is just the top of the iceberg, it seems that the change is already rolling and we are about to see some dramatic changes in automobile electrical systems.
one of the important implications as I see it, is the proffesional level of all those who deal with car electric systems and related systems like AC.

another important aspect is that 42V with high amps is already dangerous.

cars are not grounded, and some sort of protection for techs will have to be under consideration.

chemi

[Karl Hofmann]

The 42v electrical system would not be a problem for me, as for safety, good working practice means that I do not actually come into contact with live wires. What is a problem and will become a bigger problem is the fact that manufacturers do protect their software and alter it slightly as each new model is introduced, meaning that the independant repairer cannot acess much of the data stored in the ECU. The only data that they must make available is that which is linked to the control of emissions, all the rest including HVAC is dealer only. I would say that my days in automotive a/c are limited, meanwhile I shall persue my quest to install cooling systems into homes, which I feel to be potentially huge.

[chemi-cool]

hi karl,

I do not agree that AC will be a dealer only, it will be too expensive for customers and the service will be lass available, I predict that after a short time, dealers will come to people like yourself and give you all the software you will need for srvice.

with the growing number of air-conditioned cars in europe, they will not be able to handle all the work themselvs.

installing cooling systems into homes is a complete different story and the potential is huge but the marketing system should be very agresive and conduted by proffesionals and not salemen.

I do it almost every day and I know exactly what its all about.

chemi

[baker]

Some interesting subjects have been raised.

On the issue of proprietary interfaces to car electronics, I believe that there is good progress on legislation (forget where but I think the US) to force the manufacturers to open their interfaces and to follow standards.

With domestic airconditioning, there have been steps forward and steps back. Low cost, low noise inverter ductless splits are a step forward, but some of the new laws are a worry. In Western Australia, the installer is responsible to ensure that the noise from the outside unit does not exceed 35dBa, as measured from a neighbouring property. Should a neighbour complain after installation, the installer must bear the cost of relocation or sound proofing.

Discount retail price on a Fujitsu 2.8KW cool, 3.6 KW heat, R410A inverter split with 5 year warranty is 1000 AUD ($US750 or 410 quid). I am continually amazed by how cheap these things are becoming.

[Bones]

if thats the prices of a fujitsu... i would hate to think what the prices are on the cheap, cheap retail giants garbage... installation costs must be more then the unit lol

[jg/oz]

Friends,
Pretty interesting conversation but unfortunately I do no know enough about
legal implications as mentioned.

Just wander--what is your opinion about 'Refrigerant fluids" does it need to be
Low Global Warming ( lower than 50,100,150,500,1500 or what ever ) or are we relying on the containment program which does not seem to work.

Policing "containment" is extremeley difficult, but very easy to do. Have we not all being done it ?? (I have ............) In my European time 20 years ago
we were/had a Transport Refrigeration service set up. ThermoKing advised in it's manuals to vent the R12 as soon as the system was opened and add virgin
R12 in the system after repairs. We sold Tons and Tons of the stuff.

Now I think about my grandkids and they have to wait another 90 years before my actions will not harm the Ozone layer anymore.(R12 active lifespan 112 years). What would be your opinion. If you do not believe Global Warming is a future problem please do not react ,there is a forum in the USA who has very little members believing in Global Warming and Ozone depletion.

Have a look at http://www.aircondition.com

regards jg/oz

May be this is

[Karl Hofmann]

Chemi,

It is the manufacturers who protect the software, the dealers have no say, they have to pay for the equipment and software to maintain their franchise. Even if their customers have to wait they will not release this type of information to help. The problem may not even be a/c related, last year I had a diesel RangeRover with a fault that I eventually traced back to a faulty fuel lift pump in the fuel tank. BMW regularly update their sofware to deter it from being copied, they only allow Bosch to release it for use on Bosch's own diagnostic equipment after two or three years...Its a scam.

JG

I'm still not convinced that releasing refrigerants is destroying our protective layers, but I really don't want to be breathing the stuff either, so it is right that all refrigerants are recovered and dealt with under control, perhaps we should look at the aerosol industry also. Vented refrigerants are waste, just like sewage and should be treated accordingly and all REASONABLE steps should be taken to prevent leakage. Sadly the word reasonable is reliant on the gift of common sense.

[Peter_1]

In the past (25 years ago) , i had a Datsun, now Nissan.
It took +/- 30 min to change the brake pads.
In my street is a garage where they work on Mercedes.
When you wonna change the brake pads, you need a computer to open the brake 1pistons and to close them again after a brake pad change.
You also need a computer to reset the diagnosis system, otherwise you receive constant fault codes via the on board computer.

[Karl Hofmann]

Car manufacturers don't make money on selling cars, they make it on servicing and parts, and the more you are forced to go to the main agent the better for them.

Make them a funny shape and a £10 reciever/drier suddenly is a £100 component

[Bones]

In my street is a garage where they work on Mercedes.
When you wonna change the brake pads, you need a computer to open the brake 1pistons and to close them again after a brake pad change.
You also need a computer to reset the diagnosis system, otherwise you receive constant fault codes via the on board computer.

so potentialy anyone driving a merc is driving a herbie? i hope there software is alot more stable then windows lol...

nothing like stopping on the highway to restart your car after a software crash!

[Peter_1]

In Belgium we have Touring Wegenhulp (TW), a organisation who helps you - if you're a payed member - when you having car troubles along the road.
A friend of me is working at TW and the most problems they encounter are with those fully electronically controlled cars and the most problems - mostly not repairable - are with the electronics itself and often with the expensive brands (Mercedes, BMW, Audi...).

[jg/oz]

Friends, As we speak there is a Conference going on in the US of A
about MACS and it may be of interest to hve a look at the subjects
presented.

I think we may have to close the tread for a while and get information of what has been said in papers up there.

Interesting subject is:

EU Union ( at present 450 million people) have deceided that all fluids
to be used in MACs ( Motor Vehicle AC systems have to have a lower
GWP than 50 ( R134a is 1300) after 2013. So watch what US Chemical
Industry is "pushing" to keep their 134 factories running for another
nearly 10 years and trying very hard ( I mean extremely) to suggest using
R152a (GWP 140 and highly flammable) as a replacement.

'Naturalia" has hardly any funds to fight of the 'Multi million dollar" PR
campains R152a, still HC (60/40) cheap as anything can do the job even better and is able to be retrofitted ( drop in) into all R12 and R134a systems and increase performance at the same time.

R152a will do the same a bit less performing but cost wise probably 3 to 4 times more expensive. Which may bring the 3 rd world up to 2010 to revert
CFC system and R134a systems to R12 which is still overthere US $ 1.50 to
us$ 2.00 per kg.

Whats your opinion ????????????????????????????????

jg/oz

[baker]

A similar situation is happening in the computer world with the Microsoft - Linux debate. You see the same biassed reports, sides forming according to political leanings or nationalities, and lots of FUD (fear, uncertainty and doubt).

I do not expect reason or right to triumph. Rather, I expect to see greed and stupidity win, once again.

[jg/oz]

Friends,
Interesting to come accross an 'Elsevier Journal publication.

The International Journal of Refrigeration (France) with an article in next issue June.

The following article is available since Mid March via Internet and payment od US $ 30.--

Hope this will make --and cause an end to all speculation of Flammable substances in MACS worldwide.

Have a read:


Article by : Dr I.L.Maclaine-cross Uni UNSW Sydney

with following abstract see below)

Seems to me good reading and gives a final indication that Riskassessments are good indicators but also relative:

j

Usage and risk of hydrocarbon refrigerants in motor cars for Australia and the United States
Frigorigènes hydrocarbures en application automobile aux Etats-Unis et en Australie : utilisation et risques associés

I. L. Maclaine-cross ,

School of Mechanical and Manufacturing Engineering, The University of New South Wales, UNSW, Sydney 2052, Australia

Received 17 July 2003; Revised 15 December 2003; accepted 5 January 2004. Available online 12 March 2004.




Abstract:

Commercial replacement of fluorocarbons in mobile air conditioning systems (MACS) with typically HC-290/600a[60/40] and minimal precautions began in Idaho in 1993. R290/600a has low environmental impact but mixed with air is flammable and frequencies for fire, injury and cabin overpressure were predicted.

No such accidents are known from 1993 to mid-2003. R290/600a suppliers consumption, representative MACS charges and charge termination frequency were used to predict yearly total MACS numbers. Mid-2002 in Australia there were 0.33×106 and at end 2002 in the USA 4.7×106 R290/600a MACS.

Integrating over time gave usage for Australia to the end 2002 as 1.09×106 car-years and to mid-2003 for the USA 21.7×106 car-years. The measured US fire, injury and cabin overpressure frequencies are less than 3.2×10-7 per car year with high probability. This fire frequency is a hundred times lower than predicted because most R290/600a leaks in MACS use are effectively non flammable.

Author Keywords: Refrigerant; Hydrocarbon; Automobile; Air conditioning; USA; Australia; R-290; R-600a; Use; Risk


Nomenclature
Nomenclature
c
average mass of replacement refrigerant consumed in charging a MACS (kg)
C
consumption rate of replacement refrigerant for MACS in country (kg s-1)
f
frequency density of charge termination (s-1)
L etc etc etc .


AU
Commonwealth of Australia
MACS
Mobile Air Conditioning System
NHTSA
US National Highway Traffic Safety Administration
UK
United Kingdom of Great Britain and Northern Ireland
US
United States of America


Corresponding author. Tel.: +61-2-9385-4112; fax: +61-2-9385-1222


( with thanks to elsevier's website)

jg/oz

[Karl Hofmann]

So why have the Americans banned HC12 and other such garbage. If you are really determined to have an environmentally freindly cooling system why dont you advocate evaporative coolers? Be fair, no one really NEEDS auto air con

I note that you only seem to pick up on what suits your argument. We have established the fact that auto a/cs leak a lot of refrigerant, so it seems bizare to me that you should advocate the use of a flamable substance, knowing that it would leak, mix with air in an area where there is a good chance that you would encounter a source of ignition.

Those junk reports assume that the refrigerant stays inside the refrigerant system and that there is no air in there, it is not uncommon for DIYers to simply "blow" a little refrigerant into an a/c system and hope that it works!
You can produce all the reports you like, but a report is no substitute for common sense

Please go and work on some automotive a/c systems and see just how C##p they really are, perhaps then you would join the real world.

[Jasper]

I agree,
Have stopped doing any FAVOURS for freinds any more, all automotive a/c systems should be BANNED (Lets have a poll on that issue)

[baker]

So why have the Americans banned HC12 and other such garbage. If you are really determined to have an environmentally freindly cooling system why dont you advocate evaporative coolers? Be fair, no one really NEEDS auto air con

As a Du Pont spokesman wrote, the US has trained hundreds of thousands of technicians to believe that refrigerants are non-flammable, and it is not practical to change this. In a suitably regulated area, HCs are perfectly safe. In the real world, I cannot see them being acceptable for a very long time. It is the same with nuclear energy and DDT. There is a huge gap between scientific evidence and "real politik".

[Karl Hofmann]

Given the right conditions you can make a pretty big bang with a truck full of custard powder, slop a bit of diesel on to a load of fertilizer and you can make a large building disappear. My point is that many materials that are normally regarded as safe can under the right conditions can be hazardous. I am satisfied that R134a is as safe as can be reasonably expected knowing that all auto ac systems leak to a greater or lesser degree. I guess that it is all a matter of how much you are willing to risk to save a bit of cash

[baker]

Given the right conditions you can make a pretty big bang with a truck full of custard powder, slop a bit of diesel on to a load of fertilizer and you can make a large building disappear. My point is that many materials that are normally regarded as safe can under the right conditions can be hazardous. I am satisfied that R134a is as safe as can be reasonably expected knowing that all auto ac systems leak to a greater or lesser degree. I guess that it is all a matter of how much you are willing to risk to save a bit of cash

I now understand your position better. I do not use HCs because it is no cheaper when you do it properly. However, the backyard boys with their Ronson refills and BBQ propane can get a system working, but I would hate to have to work on the system next. I can see how someone who specialises with vehicles would come to associate HCs with danger and hackery.

In Australia we are changing to national regulation of refrigerants and the debate is whether HCs will come under the legislation or not. If they don't, all your fears will be realised. If they are regulated like HFCs, I would expect all the controversy to disappear over time as only trained and licensed people could use them.

[jg/oz]

Friends,

If "cash" was the main problem with HCs than I think you have never understood the issue. The basic issue you mention is safety. 20 million user years with HCs in MACS systems have proven that (without accidents) HC is very safe. ( hope you understand "user years"). It basically tells us that your
washing machine at home is much more dangerous for your family than your HC in your MACS.

Approx 600 Ton of HCs in the US are used by DIY (ers)yearly )equivalent to 1800 Ton of R134a [density difference] and no accidents occurred.

If you are a MACS technician and you do not know how to handle refrigerants I think you should leave the Industry.

For your information Australian/New Zealand Standard 1677 states that an odourizer has to be used in Commercial HC refrigerant (so called Mercaptan
smell like LPG which irritates at 25 ppm).

The main issue with HCs is Global Warming and if you do not believe in the seriousness of this issue than any discussion is useless and than you might
as well go back to R12 and the other F-gas stuff.

jg/oz

[Karl Hofmann]

If cash wasn't the issue, then what is wrong with CO2? all of the benefits, less of the pitfalls, except for the fact that the equipment will have to be more expensive. Why continue to mess around with the same old equipment when we could develop something potentially better, this is why we're not all running round in horse drawn carts.

If you would care to look a system designed for R12 you will note that it is of a far more robust construction than any modern system. The danger is when your DIYers try to patch up a leaky system, these are the same DIYers who not only begrudge paying a professional to do the job right, but also try to implement a bodged repair rather than fitting new parts, and the same DIYers who are happily pumping products like HC12 in to their cars. Dont tell me it's not a money issue!

If a motorist is driving in a car with HC in the ac system crashes due to his bodged repair to the brakes, the car hits a tree HC refrigerant escapes and catches fire toasting him and all of his family to what would the accident investigator atribute their deaths to? HCs or dodgy brakes? I hope you get my point, there are lies, damn lies and statistics.

So when I come across a car with HCs, what do you propose that I do with it? No MVAC tech I know carries equipment to deal with it. I know that you will state your standard line that it is not illegal to vent HCs to atmosphere, but what of the health and safety issue of releasing a flamable gas in to an enclosed workshop?.....With a pit?

I take the safe handling of any refrigerant as a very serious matter, as do all professionals, but perhaps some of the onus for the safe handling of refrigerants should be put on to the vehicle manufacturers, who deliberately design systems to corrode

[jg/oz]

Friends,

You don't read many accidents with a truckloads of custerd powder being blown up or fertilizer used as bomb-material with diesel.(May be Iraq).

CO2 would be the best fluid to be used in MACS but.............
approx 300 million old MACS systems are around and leaking till the end of their days. Why not use as a "intermediate" HC fluid for all the old systems and wait for the CO2 ( significantly more expensive)

Than wait in the mean time about the hundred or thousands of dead people ( as most predict) caused by exploding HC MACS and if that does not happen (as it has not happened from 1994 onwards in ustralia and America) we may deceide that HCs after all is not such a bad solution........and forget all together about CO2.

Instructing approx 1 million MAC mechanics worldwide how to handle CO2
systems and supply these people with CO2 tools cost probably billions.

Simply "drop" in and "leak out" of HCs in non-retrofitted OEM R12 or R134a systems with HCs seems to me a very simple solution for a worldwide MACS problem.Anybody ---a better solution. No BS with answers like keep the HFC in because as we all know in the end it all goes to the "GODS" meaning up.

Any HCs can be vented without problems to the environment, the use
of "natural" mineral oil would than help.

This whole conversation is a "Non" event if you do not believe that Global Warming is a serious issue.

jg/oz

[Karl Hofmann]

That the earth is getting warmer, there is little doubt, that refrigerants are to blame is almost impossible to prove or disprove. However, what ever we release to the atmosphere we must also breathe and that there is no doubt.

I cannot see the logic in marketing HCs as the solution to leaky systems. HCs can only be safe if they stay inside the system where there is no oxygen to allow them to burn. MVAC systems are not designed to safely contain HCs anymore than a powder tanker not fitted with an earth strap,filled with Custard powder.

Fertiliser bombs are poular with loonies the world over!

[jg/oz]

Friends,
If you do not believe in world biggest next problem -Global Warming
and if you do not believe that HFC are mentioned in the Kyoto Protocol as
anthropogenic Greenhouse gasses than any debate about HCs is useless.

On the other hand if you understand Risksassessments you will know that getting an explosion or fire in a MACS systems is equivalent to twice winning
the Lotto in a row.

Participating in traffic is 7000 times more dangerous than getting an explosion or fire in a HC charged MACS system.

Temperarely end of the discussion from my side.

jg/oz

NB- Uploaded a file which was a presentation last week in Washington,
may be of interest to readers

[jg/oz]

friends,

Sometimes you may think that I am over the moon with Car AC systems or MACS, but bear in mind
that those "in the know" keep telling me that MACS are the biggest polluter of Greenhouse gasses
and are nearly becoming 10/15% of "tailpipe" pollution of a car.

Some 80% of new cars by now are provided with a factory fitted AC systems, that we have
approx worldwide 400 million cars with a MACS system it is obvious that this sector
of our Industry needs some attention.

Or as I call it a "priority pollution problem" (3p) in our Industry -- "number one."

This is what MIPIGGS (latest edition) had to say about it:

NB. Those approx 400 million older CFC12 and HFC134a systems keep polluting the environment (as long as they use their MACS system before the scrap-heap) a simple change over to HCs (like already
running around in the world of 4.8 million HC MACS AC systems) would make ,in one go ,the pollution
problems of MACS a thing of the past. MACS problem solved.

For you to decide if CO2 is the answer , R152a or HCs.

CO2 Mobile Air Conditioning 'Ready For Mass Market in 2009'

French group Valeo (1) reports (July 29, 2004 - Valeo www.valeo.com <http://www.valeo.com> ) it has successfully developed an environmentally friendly air conditioning system 'which meets future EU regulations'. The system replaces HFC R134a refrigerant used in car air-conditioning systems with the R744 refrigerant 'and consequently eliminates the direct impact of air-conditioning systems on global warming due to refrigerant leakage'. The CO2 based Valeo R744 system was tested on a demonstration vehicle by automotive experts at the SAE Alternate Refrigerant Symposium in Phoenix, USA, with ambient temperatures up to 43°C in both city traffic and highway driving conditions.

"Valeo is leading the development of future of air conditioning systems in order to enhance comfort for all car occupants while minimizing the environmental impact. We expect to see these systems in the market by 2009," said Thierry Morin, Valeo Chairman & CEO.

Valeo says 'there are servicing cost benefits for the automotive industry as there will be no need to recover and recycle the refrigerant at the end of life'.

Meanwhile
ENDS magazine (ENDS REPORT August 2004 www.endsreport.com <http://www.endsreport.com> ) reports that 'US firms prefer HFC-152a which, while much less potent than HFC-134a, is still 140 times more powerful than CO2'.

Last year the European Commission published a draft Regulation setting out plans to curb emissions of fluorinated gases. The proposals include provisions to phase out gases with a global warming potential greater than 150 from car air conditioning between 2008 and 2012. The measure is aimed primarily at the most common gas, HFC-134a, which is 1,300 times more potent than CO2.

The UK opposes the ban. Environment Minister Elliot Morley told MPs that it would "greatly increase" costs to UK equipment suppliers. He also cast doubt on the safety of CO2 systems - seen as the most promising alternative - because they must be kept under high pressure and "may suddenly explode" (ENDS Report 348, pp 33-34 <outbind://71-000000004834B1067C533B45ACEF490817EFE02204A63B00/article.cfm?ArticleRef=348036> ). But Norsk Hydro, manufacturers of CO2 based cooling technologies point out that "pubs use CO2-containers at the same pressure as MAC every day". ENDS notes that 'Japanese air conditioning manufacturer Calsonic Kansei, whose main European production facilities are in the UK, says that because of the small amount of CO2 used in such systems, the power of any explosion would be comparable to releasing an ordinary CO2 fire extinguisher. Furthermore, prevention measures such as pressure relief devices have been developed to relieve the risks of an explosion

Instead, the main risk is considered to be the toxicity effects of CO2 leaking into the car. Such a leak would be difficult to detect because of the background levels of CO2 in the atmosphere and the CO2 produced by passenger exhalation'.

ENDS says "US air conditioning manufacturers such as Visteon and Delphi, plus compressor manufacturer Sanden, are pushing for HFC-152a". In the past the HFC industry used the flammability of hydrocarbons as an argument against them. ENDS notes that both Calsonic and fellow Japanese manufacturer Denso have already launched CO2 systems in hybrid vehicles in Japan. Europe's biggest manufacturer of car air conditioning systems, Behr, said it is ready to produce a CO2 system for any type of car and have it on the market within two to three years. "We expect some car manufacturers to move to CO2 soon," a spokesman told ENDS.

Audi and BMW are expected to be the first to introduce such systems on series production vehicles, possibly between 2006 and 2008.

(1) Valeo ranks among the world's top automotive suppliers. The Group has 128 plants, 65 R&D centers, 9 distribution centers and employs 68,800 people in 25 countries worldwide. www.valeo.com <http://www.valeo.com/> Press Contacts:
Alexandre Telinge / Sophie Porte +33 140 55 20 74 alexandre.telinge@valeo.com <mailto:alexandre.telinge@valeo.com> , sophie.porte@valeo.com <mailto:sophie.porte@valeo.com>

best regards

jg/oz

[jg/oz]

Friends,

Always interesting to read that others are thinking in similar ways as we do. If those in higher office are
talking about it than it's going to happen one day. When.............!!! I hope soon and advice all those involved to be prepared for a new very profitable rally.

Have a read:


** SPECIAL MIPIGGS UPDATE **
UK Opposition Call For Ban on HFCs

The Rt. Hon. Michael Howard QC MP, Leader of the Conservative Opposition party in the UK and a past Environment Minister, has called for a phase out of HFCs and said "climate change is one of mankind’s greatest challenges".

Speaking on Monday 13 Sept, to a large audience of environmentalists, politicians, industrialists and the media, at an Environment Forum organised by Green Alliance/ERM he announced that "the Conservatives are committed to phasing out the use of hydrofluorocarbons, or HFCs, between 2008 and 2014". He continued, saying that "HFCs have solved one problem - they do not damage the ozone layer. But they have caused another – they contribute significantly to global warming. Their impact is some thousands of times greater than CO2. HFCs currently account for two per cent of the UK’s greenhouse gas emissions and that will have doubled by the end of the first decade of the twenty first century".

Howard also cited companies who were already tackling this problem like "Coca Cola – which owns around nine million refrigerators worldwide – is to phase out the use of HFCs in its refrigerators. Unilever has taken a similar stance, and Toyota is introducing non-HFC air-conditioning in their cars. These companies recognise that HFCs are not the way of the future".

Howard finished by saying that "These are welcome, but isolated, examples. Unless this issue is addressed as a matter of some urgency, and government gives a clear lead, then the situation will only worsen. That is why a future Conservative Government will work with our European partners to phase out the use of HFCs over the next decade".

Speaking the next day, at the 10th anniversary of the Prince of Wales’s Business and the Environment programme, the Prime Minister, the Rt. Hon Tony Blair MP called climate change the world’s greatest environmental challenge. He said that "our effect on the environment, and in particular on climate change, is large and growing". He said "that there is no doubt that the time to act is now. It is now that timely action can avert disaster". He spoke of the potential for innovation but said nothing about control of HFCs.

The next General Election in the UK is widely predicted to be in the spring of next year. Blair said the challenge to tackle climate change was "complicated politically" as "there is a mismatch in timing between the environmental and electoral impact".

Michael Howard’s speech can be found at http://www.greenalliance.org.uk/ <http://www.greenalliance.org.uk/>

and Tony Blair’s at http://www.number-10.gov.uk/output/Page6333.asp


regards

jg/oz