programmable thermostat

[Guest]

i changed an old 2 wire thermostat with a new programmable thermostat but it is not functioning properly. my AC won't stop running. anyone know how to wire it properly?

[Guest]

Is the new thermostat rated for cooling as well as heating, i.e. it should switch on when the temperature increases and off when it drops below the setpoint. Heating thermostats do the opposite. Most can do either duty - if they have both a normally open and a normally closed contact. Check the terminal identifications - there should be something like COMMON, NC and NO. One of the wires should go to the COMMON terminal. Try changing the other one.