trooz wrote:
> I was told that one cannot simply add 134-A to a cooling system that's only
> blowing about 57 degrees.  They said the system had to be totally evacuated
> and then filled with a precise amount.  Anyone know about that?  I've always
> had Freon added in the past (it's been R-12 until a few months ago when I
> had the system converted to 134-A).  Is this something peculiar to 134-A or
> just peculiar to this shop?  They're talking close to a couple hundred
> dollars to do it.
>
> Bob Trousdale
> '90 Westy
>
>
>
I think you are getting a snow job from the shop. If they have the
proper guages they can determine exactly how much needs to be added
without going through all that.

Now that you have already converted to 134a, you can legally step up and
convert to a blended refrigerant like Freeze-12, which will give you
performance within a gnats whisker of the original R-12, and is a lot
cheaper. The rules regarding all this are an abfuscation in my opinion,
but if you really dig into it, you discover that legally you can't go
directly from R-12 to a blended refrigerant like Freeze-12, but by
regulation you must first convert - using all the proper steps - to
134a, then from there you may convert again - using all the proper steps
- over to the blended refrigerant. I think the legal beagles were trying
to avoid some kind of problems if they said it was OK to convert
straight across. No mechanical reason you can't, just legal reasons -
it's the rules.

Good luck,

John Rodgers
88 GL driver