Auto Parts: buick climate control, buick century, climate control

Question
97 buick century w/ climate control. Heater works but system seems to be losing it's ability to tell what the temperature is.  When it's set for automatic, I can set it at a certain temperature and the system takes over and keeps the car at that temperature. The fan speed also changes automatically.  Lately, I have to set the temperature at a higher setting to get heat and the fan blows cold air for awhile even though it "thinks" it's blowing warm air. I've gone to just adjusting fan speed manually and not using the "auto" setting anymore because the fan will blow cold air on high speed.  When I restart the car with the engine warm, it still takes 5 -10 minutes for the warm air to return.  I don't know if it is a climate control problem or thermostat problem or something else.  Can the climate control be repaired or parts replaced or does the whole unit have to be replaced?

Answer
i would start with the little things first...Try replacing the thermostat first..Its hard to diagnose things like this. Being that the vehicle is a 97 its probably time for a new thermostat. Replace it and Im sure this will fix your problem! If not,.. start to take note of any electric problems and take it to get diagnosed! Good Luck