Technical 64-66 c10 with ac question

Anyone have a 64-66 chevy C10 with a working factory a/c unit? I have a question about the knobs and how to use them. The manual doesn't quite make sense to me. Or possibly I am over thinking things. Thanks

 

I used to have one, but it's been over 20 years....the AC did work. If you remind me what the knobs are, and ask your question, I might be able to remember. Oh...here's a pic of the knobs from the internet.



Pull the top one to get air through the AC system. Pull the lower one as needed, it controls temperature. The middle one will get air from outside if you leave it in, and inside if you pull it out. The fan control on the heater panel runs the blower motor. I think you leave the other heater controls off.

 

Squirrel is amazing.

 

Here is my issue. The manual states that the defost and temp lever be in the off position for the ac to work. Pic (2). Now only way I can get ac to the center ac vent is to move the temp (heat) lever down pic (1) The further down the more comes out of center vent.

Now if I shut the ac controls knobs off no heat or anything will come out of the ac center vent.

The last pic is the manual and what it states. This is why I am confused.

Hopefully I didn't cause to much confusion with my explanation.

 

You are correct with what the knobs do. Center is for recirculating.