Auto Air Conditioning & Heater Repair: 1999 GMC Suburban - air not blowing out vents, gmc suburban, vacuum hose

Question
Thanks for this site!  My son and his friends took the dash off to put in a new stereo.  Now, when I turn on the air or heater, it runs fine but the air does not blow out any of the vents. I've heard he may have disconnected a small vacuum hose but we cant find anything.  Any suggestions?  

Answer
HI Kelly

Pull the control out and check all lines for good connection.  If you have an automatic ac control then you will not have vacuum.  They work with actuators.  Disconnect your battery and se if maybe it will just reset for you when you reinstall it again.  Let me know and we will go step by step.