Help on a/c direction

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Joined
Feb 20, 2020
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North Georgia
My Car
1972 Mach 1 dark green
I had the center pod off of my car which, of course, included the air control panel.  I did have the dash pad off but I do not think I did anything with the duct work (although I did touch it at some point).    Anywho, now the a/c  mainly just blowing thru the defrost vents, the high/low setting works diverting air to floor and defrost but nothing really coming from the vents..  I cannot imagine plugging in the vacuum plug incorrectly?   Everything worked as it should before I took out the control panel.  I did find the vacuum line from the manifold to the canister was off, re attached it but no change.

 
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BUCKWHEAT

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Jul 22, 2021
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Location
Warson Woods, MO
My Car
1973 Gold Glow Mustang Convertible, 302 2V C4
I have a new-to-me 1973 convert.  The squirrel cage makes lots of noise and no air to speak of comes out anywhere.  I took off the dash pad. The ducting hard plastic tubes slide into each other so loosely that (I think) the air flow is lost under the dash.  I am replacing the heater core and intend to use that thin silvery HVAC tape (not "duct tape") to cover all the plastic tube connection joints when I put it back together.  I am making the brash assumption that I will have all the vacuum doors, etc, working after re-do.    

 
Joined
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993
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North Georgia
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1972 Mach 1 dark green
i was just thinking before I saw this that maybe I pulled on the top plastic tube just a little and perhaps it seperated from the part that goes to the vents.  Guess I will pull the dash pad and check, thanks

 
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1972 Mach 1 dark green
well it turns out the culprit was the ac heater control valve switch (behind the glove box liner).  When I had the liner out I saw the switch was old, original and was just a hair shy of closing all the way when the temp is turned to the coolest setting.  I put a new one in, and in the process of putting back the liner with the extra fuse box I have in it, I knocked off one of the vacuum lines to the switch.  So when I started the car there again was the air blowing from the defrost vents, not the dash vents.  I then saw the air conditioning water control valve , the one on the water line in the engine compartment was not closing, that is what the ac heater valve switch does.   So when I looked at the new switch I had just put in I  saw the vacuum line off and re-connected it everything then worked.  Water line closed in the engine compartment and the air was now blowing out of the dash vents as well.

 
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