Goodbye R143a; Hello HC12A

[antonmnster]

Comparing HC refirgerant to propane cylinders is totally apples and oranges.

Propane cylinders are pretty robust. If you have a car accident severe enough to rupture on in your passenger compartment, you're merely saving your family cremation expenses.

A refrigerant in a high temperature, high pressure state located in a thin metal coil at the very front end of a car, however, is going to explode and/or ignite very easily upon any impact. The location of the condenser and the state of the refrigerant while the system is on couldn't be more of a fire hazard! It's not going to incinerate the car, but it probably will ignite other things in the engine bay.

How often are people knocked unconscious or need to be extracted from a car after a collision? Adding a fire to an otherwise minor collision might not help.

This stuff has been around for decades, but running it would be totally negligent, IMHO. Actually, I thing it would have to be characterized as pretty stupid.

 

[MegaCorp]

They have been running propane cars and taxis for 35-40 years. They have a rear LPG tank and hoses and tubing running to the engine where a regulator fuels the engine. Never heard of a fire or accident with these systems, in fact I would say gasoline is for more dangerous. (can you imagine the safty furor if we all had been driving electric cars, and someone wanted to bring a gasoline powered car to market!)

I think a little in the AC is a non-issue. I am guessing DuPont is behind the safety scare as they won't be able to gouge consumers as they are now with the price of R134a

 

[antonmnster]

Yeah, there have been lots of propane-powered cars around for a long time. But again, that's a totally meaningless comparison.

In order for that argument to work, you'd have to accept that a ac condenser located in the front of the car (ahead of any crumple zone) is as unlikely to cause a fire in a collision as a propane storage tank located in a much less damage-prone spot. No one can seriously argue this.

And the amount of propane isn't nearly as relevant as it's likelihood of escaping and finding an ignition source - a fairly high probability since an a/c condenser is going to be about the second thing to break - even in a very minor collision!

There's a reason this stuff is illegal. And it doesn't take a tinfoil hat to see it.

 

[Kestas]

Originally Posted By: antonmnster
There's a reason this stuff is illegal. And it doesn't take a tinfoil hat to see it.

The reason may be more political than technical. I'm a proponent of HC refrigerants and I believe the hazards are minimal for all the reasons posted above.

 

[Drew2000]

Legal Status of HC-12a, Duracool 12a and OZ-12

8. What other regulations restrict the use and handling of hydrocarbon refrigerants?
In addition to the prohibition on use described above, and the federal law banning the venting of all refrigerants, there are also state and local statutes and regulations that relate to certain uses of hydrocarbons. As of the printing date of this fact sheet, EPA is aware that the following states prohibit the use of flammable refrigerants in automobile air conditioners: Arkansas, Arizona, Connecticut, Florida, Idaho, Iowa, Indiana, Kansas, Louisiana, Maryland, Nebraska, North Dakota, Oklahoma, Texas, Utah, Virginia, Washington, Wisconsin, and the District of Columbia.

Automotive Substitute Refrigerants

 

[mechtech2]

As I recall, you may have to run at higher pressures.
This would not be good for parts designed for lower pressures.
Better check into it.
And R134a is not horrible. Some cars have lousy AC, no matter what. Some are fantastic with R134a.

 

[Bluestream]

No, the pressures are actually much lower than R134a.

This study "This fire frequency is a hundred times lower than predicted because most R290/600a leaks in MACS use are effectively non flammable.


Link

 

[cp3]

From what I'm finding the auto ignition temp is higher for HC12a that for R134a, by around 200*F and seems to have a fairly narrow flamability limit. Any reports of this causing fires in auto acidents?

 

[Bluestream]

The manufacturer has a 3 million dollar insurance policy for just that reason. No one has yet to make a claim.

 

[Shannow]

Originally Posted By: antonmnster
In order for that argument to work, you'd have to accept that a ac condenser located in the front of the car (ahead of any crumple zone) is as unlikely to cause a fire in a collision as a propane storage tank located in a much less damage-prone spot. No one can seriously argue this.

You'd also have to accept that in a serious collision, the system would depressuruise almost instantaneously, removing the fuel source from the scene pretty quickly.

 

[xxch4osxx]

Here is a part of a page from the Duracool website concerning flammability of HC refrigerants:FLAMMABILITY

Is DURACOOL® flammable?
Like all hydrocarbons, DURACOOL® is flammable, and must be handled accordingly. Practically all lubricants, additives and oils used in the engine of a car are flammable. Gasoline is flammable. Hair spray, deodorant and whipped cream aerosol propellants are flammable. All must be transported, handled and utilized (or installed) using safe practices and following instructions where possible.

Have there been studies to determine the potential level of incidence, in terms of ignited automobile compartment leakage?
Internationally respected risk assessors Arthur D. Little, in a detailed UK-based study, estimated the risk of an ignited refrigerant leak in the passenger compartment of a motor vehicle as being in the area of 3 in 10 million. Their findings, from a local perspective, mean that if every car in the USA (some 50 to 60 million vehicles) were to use a hydrocarbon refrigerant such an accident might occur once in every 50 years.

What would the impact of and "incident level, once every 50 years" ignited automobile compartment leakage actually be?
In terms of the "impact", it is important to recognize that automobiles generally have 12-15 ounces of DURACOOL® refrigerant. If there were a full amount leak into an automobile compartment and it ignited, it would theoretically create a "flash" which would last 1-1.5 seconds.

There are eminent Risk Assessment Reports available which document the safety of hydrocarbon refrigerants in motor vehicle air conditioning systems.

What is the difference between regular propane and the refrigerant propane that is used to manufacture the DURACOOL® products?
The propane that is regularly used for barbecues, and general consumer or commercial use is a by product or deritive of the hydrocarbon manufacturing process (the production and refining of raw oil products). The propane used for standard applications (such as your home barbecue). In order to utilize the product as "refrigerant grade" the product is further refined to render out methane gases and other impurities. This refrigerant propane is different in many ways, most notably is the disparity in the auto ignition. Essentially this refining makes the product safer and more stable. The Auto ignition for regular grade propane is ~842 F., while the DURACOOL® products auto ignition is ~1635 F.

Why does DURACOOL® have the scent of propane?
The additive "ethyl mercaptin" is actually a stenching agent that is added for safety reasons. Mercaptan, as it is commonly known, is added to natural gas, propane, butane and virtually all gases as an agent that will alert the user to any leakage. The addition of mercapan should be viewed as a safety feature (see below). Mercaptan is also condensable in the AC system and can not limit performance in any way and will not negatively impact components. The mercaptan smell is not detectable under regular working conditions or under normal install conditions.

Note: It is important to recognize that, whether a refrigerant is toxic or flammable, the risk of leakage into the automobile compartment is very, very minimal. The great thing about DURACOOL 12a® is that the product provides for a built-in safety feature that ensures IMMEDIATE notification to the driver and the drivers family when there is a leak. This safety feature is the addition of 'mercaptan' and this feature is not available with
R-134a. Overall, the safety aspects of the DURACOOL® Refrigerants by far outweigh those of the toxic alternatives available today.

 

[Gary Allan]

Forgive us. We're made sissies. Our mothers even ask us if we have clean underwear on before we go out just in case we get in an accident and have to go to the ER.

 

[Bluestream]

Originally Posted By: Gary Allan
Forgive us. We're made sissies. Our mothers even ask us if we have clean underwear on before we go out just in case we get in an accident and have to go to the ER.

Gary, you should have been a comedian! (Or political commenter)

 

[rshaw125]

Originally Posted By: Bluestream
The safety issue is nothing but a Red Herring. I am more concerned gasoline in my fuel tank and about the possibility of current toxic R134 leaking into the passenger compartment than the flammability of HC12A. Everyday I see Propane delivery trucks on the road with huge tanks of propane on the back, and if that is considered safe why not the 9oz for my Grand Am.

Anyway, I am eager to see how it works for myself..


Been using Enviro-safe for 4 summers now. 100% happy with it.

 

[Tempest]

It defiantly is flammable.



Right about 4:10.

 

[severach]

Sure it's flammable. Leakage outside the cabin is a non issue. The HC leaking from the condenser and engine would be among the safer things leaking during an accident. The only place where HC was in question was a leak in the cabin large enough and near enough to a spark event to cause an explosion.

This video was the best demonstration I've seen that a leak in the cabin is a red herring too.

 

[Kestas]

To add to this discussion, I'd like to point out that there is a new refrigerant on the horizon. Europe is phasing out R134a by 2017, and introducing HFO-1234yf as soon as late 2011. This refrigerant is somewhat flammable - more so than R134a - and will require training of a/c techs to handle this new refrigerant. It's also more expensive than R134a, and will require its own fittings, manifold gauges, etc. These cars will be imported to the US, so we will need to know how to service them.

HFO-1234yf is manufactured by Dow. I'm very suspicious of a company that comes out with a new refrigerant every time the patent on their old refrigerant runs out. I sincerely believe that this anti-HC sentiment is strongly fed by corporate muscle.

To me it makes more and more sense to use HC refrigerants.

 

[OilNerd]

It's worth noting that the cars employing the new non-HFC flammable refrigerants will probably use secondary loop systems, that is, the the evaporator will cool a fluid which will be used to cool the cabin, somewhat akin to way a conventional car heater heats the cabin. This reduces the risk of flammable gas entering the cabin.

Direct cooling systems will need flammable gas detection systems.

 

[Kestas]

The HC refrigerants on the market are formulated with mercaptan. The occupant's nose is a flammable gas detection system.

 

[xxch4osxx]

Most people I see who are against hydrocarbon refrigerants are a/c techs who don't like people doing their own a/c work. They will have to realise that hydrocarbon refrigerants are the way of the future due to being environmentally friendly. Up here in Canada, there are no laws regulating hydrocarbon refrigerants and you can buy recharge kits at most auto parts stores. I have been using HC refrigerants in my personal vehicles for over 10 years and find them to work just as good as R134. The compressors usually run alot quieter after I install HC refrigerant as well.