Sounds like the heater control valve/ blend door. The actuator may be stuck or broken. The actuator opens and closes to adjust for the heat setting in the car. You might be able to take a coathanger and manually open the door if you can get to the control arm. They are usually hard to get to and pretty expensive. It is located under the dash at the heater core box. Good luck.
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Sounds like the heater control valve/ blend door. The actuator may be stuck or broken. The actuator opens and closes to adjust for the heat setting in the car. You might be able to take a coathanger and manually open the door if you can get to the control arm. They are usually hard to get to and pretty expensive. It is located under the dash at the heater core box. Good luck.