There are sniffers for hydrocarbons (I have one), but I'm not sure if
it would work for R134a. They aren't cheap ($200-300).
Most automotive shops looking for a leak in the AC system will add a
luminescent dye to the system, then illuminate the hoses with UV
(blacklight), which will cause the dye to fluoresce.

On Jul 15, 2006, at 10:24 PM, BJ Feddish wrote:

> The AC in my 83.5 Westy has a leak. It was converted to R134a a few
> years
> ago but it never worked right. It leaks out pretty fast. Is there a
> way to
> determine where the leak is? Also, is there some "sniffer" to make
> sure none
> of it is leaking into the passenger area?
>
> The irony of it all is I bought this van 8 years ago because it had
> AC.
> Passing up shiny 87's,e etc. w/o AC at the time.....