> Date:    Sun, 20 Jun 2010 12:33:22 -0700
> From:    VW Doka<vw.doka@GMAIL.COM>
> Subject: Re: Freeze-12 and other A/C supplies
>
> Yeah... the good reasons are usually $$$s provided by lobbyists to
> protect their company's interests...
>
> Jeff
>
>
> On Sun, Jun 20, 2010 at 7:56 AM, Dave Mcneely<mcneely4@cox.net>  wrote:
>
> "there are good reasons that regulatory agents rule against a product
> and that manufacturers recommend that things be done in a certain way"
>

Yeah right - clearly that's why Dupont lost the Freon/R-12 battle with
the EPA.

FWIW, Freeze 12 *is* approved by EPA for auto A/C retrofitting
(http://www.epa.gov/ozone/snap/refrigerants/lists/mvacs.html).  There
are a few problems with Freeze 12;

1.  It's 80% R-134a and 20% R-142b, i.e. its an azeotrope
(http://www.epa.gov/ozone/snap/refrigerants/refblend.html).  Neither the
R-134a, or the R-142b used to keep head pressure down, carry oil as well
as does R-12, so compressor lubrication will suffer over the long haul.

2.  As an azeotrope, using Freeze 12 in a system with leaks will result
in the lighter smaller molecule leaking at a higher rate, and thus
changing the mixture.  To recharge the system, you need to evacuate
first, not just top off.  Freeze 12 can't be recovered with R-12
equipment or R-134a equipment, so you'll have to find a shop set up to
recover Freeze 12, which may be very difficult depending on where you are.

So yes, you can use it, and yes it works well.  You just have to
understand the downsides and make allowances.  Every shop that does A/C
has everything needed for R-134a; Freeze 12, not so much.  R-134a *will*
run at higher head, and will not carry oil as well (although the PAG and
POE oils are not bad) so an old tired vanagon compressor may not hold up
as well as you'd like.

Keith Hughes
'86 Westy Tiico (Marvin)