[Vwdiesel] Alternative and combustable refrigerants

[Val Christian]

The biggest risk, as I understand it, is that the butane / propane,
will revert quickly to a gas state, and in doing so there will be
localized mixing.  Furthermore the combustable mix, at atmospheric
pressure is with wide lattitude.  Finally, condensors are typically
mounted at the front of a vehicle, the one part most often 
damaged in MVAs, even one car MVAs.  The rapid mixing, wide combustable
mix, and release of kinetic crash energy with frictive (spark)
components, create ample opportunity for a small tactical fuel-air
bomb.

FWIW, five teens recently died locally, when an improper lane change
put their gas powered SUV head-on into the tractor of a truck.  
(Search terms: Fairport grads, Bloomfield )  From one of the 
girls following them, death was not instant, although the fireball
was.  Their injuries and shock prevented them from rapid escape.
The truck driver (diesel truck) exited his vehicle and tried to assist
their escape.  Atomized fuel from the violent impact had showered 
the area.

Propane / butane and other gases may work well, and be cost effective 
as refrigerants, however their physical properties, combined with
an unprotected location on the vehicle, and with placement
within the passenger compartment, adversely impact crash survivability.


Val


> 
> In a message dated 7/12/2007 10:31:17 AM Pacific Daylight Time, 
> bobs at chemdec.natsci.csulb.edu writes:
> 
> > I would suggest NOT using butane as a refrigerant in your a/c system!  Do 
> > you really want a flammable gas being pumped into the cabin of your vehicle 
> > with you?  All it would take is a small leak under the dash to turn your car 
> > (and you) into a crispy critter.
> > 
> 
>   I talked to an engineer about that issue and he said for one, you 
> pack around 10 to 20 gallons of a highly flamable liquid (gas) and 
> think nothing of it.  (of course we drive diesels, but...)  Other 
> points he made is that the air/fuel ratio where propane or butane 
> will actually burn is much narrower than with gas.  He said the 
> odds will be heavily in favor that the concentration will be too 
> high or too low to burn.  In an accident it'll leak outside and 
> dissapate quickly.  Then there's the issue that freon exposed 
> to flame creates phosgene gas and nobody complained about 
> that.
>   Butane or propane seems to be more safe than it would seem.  
> Leaks would be easier to detect too!  ;-)
>      Loren
> 
> 
> **************************************
>  Get a sneak peak of the 
> all-new AOL at http://discover.aol.com/memed/aolcom30tour
> _______________________________________________
> Vwdiesel mailing list
> Vwdiesel at vwfans.com
> http://www.audifans.com/mailman/listinfo/vwdiesel
>