Officially, just so people know, HydroCarbon refrigerants are not allowed
in all states.  From the EPA website about HC refrigerants
(http://www.epa.gov/ozone/snap/refrigerants/hc-12a.html#q9)

The following 18 states ban the use of flammable refrigerants such as
HC-12a� and DURACOOL 12a� in motor vehicle air conditioning, regardless of
the original refrigerant: Arkansas, Arizona, Connecticut, Florida, Idaho,
Indiana, Iowa, Kansas, Louisiana, Maryland, North Dakota, Oklahoma, Texas,
Utah, Virginia, Wisconsin, Washington, and the District of Columbia.

Therefore, it may be hard to find technicians in those states willing to
work with these products.  You may be able to have a shop evacuate your
old and draw a vacuum on your system and then add the HC12a or Freeze12 at
home later.

I don't know what the penalties are for using this stuff in the above
states.  Just a FYI.

YMMV,

Martin Green

2002 Chevy Malibu
1997 Volvo 960
1982 Volvo 245T (soon to be Ti)
1977 Volvo 244
1974 VW Bus (Carb fire - waiting to rebuild)
1972 VW Camper (basketcase - waiting for paternity leave to strip for
paint, rebuild corvair engine!)

On Thu, 17 Jun 2004 02:40:34 -0400, Kim Brennan <kimbrennan@MAC.COM> wrote:

> Technically, no, you don't have to change the oil. Officially, in the
> US, yes you do.
>
> The USDOT, requires that vehicles using Freeze 12, Duracool, HC 12a and
> other similar products must first have been converter to R134a fittings
> and oil and be properly labeled.
>
> However, as I have commented before, and Glen Smith echos, these other
> freons are GREAT in Vanagons.