We are having trouble with our AC.We set the thermostat for 74 but the system just keeps on running and won't shut off down to a colder temp....Brings the house down way too cold....We have had a serviceman here about 3 times and replaced the thermostat twice with no results. He tells me maybe we have to move the thermostat...Any one got any ideas??

Is it wired and programmed properly? How about new batteries?
Eric