When an Air Conditioning (AC) system is not working at its peak, that often becomes apparent in costs and comfort. Sometimes systems continue to provide comfort even when they are poorly maintained, however, although they usually cause higher (hidden) utility costs. How can air conditioning provide comfort if it is not working at its peak? Once you have set the temperature on your thermostat, for instance, to 69°F, the thermostat will keep the AC unit running until the room