Before calling, check the power by looking in the breaker box to see if any switches have tripped. Make sure the thermostat batteries are working. Inspect the air conditioner for ice on the copper line, and if you find any, turn it off. Once you've done these steps, you can contact Aaac Service Heating and Air in McDonough at 770-875-4113 for residential A/C repair. They are open on Saturdays and Sundays as well.