Actually, air conditioners do more than just lower the temperature. They also remove humidity from the air. This could be what the original poster was referring to. Sadly, all thermostats and air conditioner controls look at only the temperature, not the temperature and humidity. That is why you have to modify your settings based on the every changing weather. On a warm day with dry air, a setting of 75 degrees may be comfortable. On a very humid day, a setting of 75 degrees may feel like it is still too hot.