I have a 69 Camaro, factory air with the following changes. Old Air POA
update, larger more efficient condenser and a Sanden 508 compressor using
R134 Freon. The gauge readings (with an ambient temperature of 83 degrees
and unknown high humidity) were 24-42/170-180 with 48 oz.(4 12oz. cans) of
freon and the engine running at 1100 RPM with a stationary cooling fan in
front of the condenser. The problem is that before the low side pressure
switch (on the POA update) turns off the compressor (due to low
pressure...24 lbs.) the A/C cools very well but, as the low side pressure
rises, so does the cabin temperature. After adding 36oz. (3 cans) I
thought
it was acting this way due to low freon so I added the other 12 oz.
without
much change except for a slight rise in the high side. I'm trying to
figure
out why this is happening and if I can get the low side to run at a more
constant range so the pressure switch won't cut of the compressor as
frequently. The pressure switch is adjustable but I fear going too low,
freezing up the eva****ator, which would starve the compressor of oil. Does
anyone know what my problem might be or how I could find out? Thanks
