2006 e 250 only blowwing air out defroster vents
One of your mode/blend door actuators is acting up. Common problem on these trucks. Check out http://www.heatertreater.net they should have a video to explain how to fix. If not there are some on you tube. Hope this helps
Check for a disconnected vacuum hose at the intake manifold. If the system loses vacuum it will default to defrost. HTH. -Jim
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