Chevrolet Repair: 1988 Chevy 1500 Heater Problem, chevy 1500 truck, 1988 chevy 1500

Question
I have a 1988 Chevy 1500 truck.  The heater stays on all the time.  I can not control the temperature of the air.  If I change it to vent, it still stays on floor heat.  Also, them temp is always hot, I can not change it to cool.  Any ideas?

Answer
Check to make sure you have vacuum to the heater control.  If it is an electric controller see if the rods fell of the actuators on the drovers side near the gas pedal.  If all the rods are there and the actuator does not move you could have a bad actuator or a bad controller.  Have seen both go bad.