The heater works for about an hour after the car is initially started. Then the air stops But the blower still sounds like it is working. When I come to stop the actuator doors sound like close doors close making a very loud air rushing noise but still no airflow.

If I shut the engine off for 30 to 45 minutes everything resets to normal. We are on 1300 mile trip home and cannot repair on the road but is there a way to get the doors to open manually or is this a relay or vacuum hose issue