Chevrolet: temperature goes up when the A/c on, temperature gauge, thermastat

Question
Anytime I turned on the aircondition the temperature gauge goes up.. and when it gets to 7.5 levels the car started blows hot.

Answer
Tundee ;
Hi -  I would have a look at the cooling system check all hoses and belts, and check the thermastat. have the system presshure tested for leaks.

than if nothing - I would flush the system . replace the thermast add new coolant , and if hot air is blowing out the a/c you should have it serviced. or recharged.  ok