Those things were replaced but not the hoses.

On Mon, Sep 27, 2021 at 7:38 AM Steve Bonde <seb007@live.com> wrote:

> You may want to be careful with this Freon (152a). While it’s considered a
> substitute for R 12, it is flammable where 134a is not.
>
> Molecule size isn’t really the issue. The tetrafluoroethane used in 134a
> is much larger than the difluoromethane you’re suggesting without the
> flammability.
>
> R 401a is a mixture of 152a and 124, and has a much lower flammability.
>
> When you made the change, did you replace the oil, filter, and drier as
> well?  That was the problem with my pickup.
>
> Sent from my iPhone
>
> > On Sep 26, 2021, at 9:48 PM, John Rodgers <jrodgers113@gmail.com> wrote:
> >
> > The summer is most gone and so is the need for AC but it sure was nice
> to
> > have earlier. Back when I had my '88 van, I dutifully switched my system
> > over to R-134a because R12 was going out and what little was available
> was
> > astronomical in cosy.  I changed the service fittings, purged the system,
> > then vacuumed the system, and added the appropriate amount of 134a. This
> > was in spring. By mid summer the refrigerant pressure had dropped and was
> > no longer cooling properly. I added 134a and brought it back up to speed.
> > By fall of the first year the pressure was back down. This was a
> > puzzlement. there was no sign of leakage any where. I didn't refill it as
> > cooler weather had set in but I knew the problem had to be solved by
> spring
> > when I had to service it again.
> >
> > During the winter I stumbled across a discussion about molecule size of
> > various refrigerants and how their sized was affected by hose design. It
> > would seem that 134a has much smaller molecule size than R12, and
> > consequently the stuff over time would leak right through the old
> original
> > hoses. And the original hoses is what I had. While pondering this
> > situation I stumbled on a video of Dustaway keyboard and computer cleaner
> > being used as a refrigerant to service the AC SYSTEM. Supposedly the
> specs
> > were similar to R-12 at least in molecule size so there should be only
> > minimum leakage. It works great as a refrigerant cooling with the best of
> > them. and I haven't changed or added to the system for a couple of years.
> > You can find videos on Youtube about this. And if you decided to try it,
> > make sure your can says on it somewhere CAS 75-37-6
>