My 240 '89 B230F has recently undergone a retrofit to R134a. All done decently well, as should be, and no leaks, it cools OK. It has been over 1 month now.

My car is the older dial and expansion valve type, with the dryer near the front.

Question: As I understand it, the dial controls the cycling of the compressor, and it acts like a 'thermostat' by sensing the temperature at the evaporator (via the copper wire going there).

My controlability of the cycling from the A/C dial seems to work very well, at minimum (12 o'clock) it cycls ON little and mostly OFF, at max (around 6 o'clock), it cycles much more ON and very little OFF, to provide for a colder evap.

My vents temperatures are not great at all, when it gets REALLY HOT in the sun in the car I can almost say that the cooling is not sufficient (sorry no temperatures to provide).

No MAJOR difference when I keep the condenser cold by spraying water on it, or by driving on the highway.

I believe to have correct amount of R134 in there, around 28-29 oz, with low pressure at 45 and high up to 230.

What else might be wrong? Can I assume that this is how cold it can get seeing as the thermostat A/C dial cycles ON/OFF the compressor as expected, implying that the evaporator actually does reach adequate coolness?

Hoping the A/C masters can help with this one. Thanks in advance.

Greg Mustang
Montreal - Ottawa
Canada