Rule of thumb is, start car cold, turn you system to vent(this keeps the A/C off), and turn your system to full cold......this brings in ambient air......now turn the A/C on.....ambient air should drop a minimum of 30F.....
So if ambient air was 90F, the air with A/C on, should drop to at least 60F....if it 60F or less, the A/C is working OK....
Output air from your registers, depends on ambient air temp, humidity, and running pressure in your system....
