Working
with three 'almost identical' vehicles makes this test worthy of a closer
look. We've charted the high pressures, low pressures and vent temperatures
for each of the refrigerants to provide an easier comparison. You will notice
that in the case of these three Cadillacs, R-12 and R-134a developed almost
identical HIGH pressures of 175 p.s.i. while the R-152a was noticeably lower
at only 165 p.s.i. Those lower head pressures will help in hotter climates!
As
you can see, the LOW pressure readings provide a little different story.
R-12 was 'right on the money' where it should be. Although R-134a was slightly
lower at 25 p.s.i., it didn't do as well with vent temperatures (below).
R-152a returned the lowest low pressure at only 22 p.s.i. That's still
acceptable.
This
chart shouldn't be much of a surprise to most. Of course, the R-12 provided
the best vent temperatures at 40ºF while the R-134a system was considerably
higher at 47ºF. But take a look at the R-152a system! It provided an
outlet vent temperature of 45ºF. That is certainly acceptable!
Comments
and questions?
What's
it all mean?
This
comparison test provides an excellent hands on look at these three refrigerants
operating under almost identical conditions. We wouldn't go as far as claiming
that R-152a is the best replacement for R-134a based on just one simple test...
but when you look at the facts and figures, you would have to agree that
it's certainly a candidate for automotive applications. You can read more
about this in Keepin' Cool, autoACsystems.com new eZine dedicated to mobile
A/C.