Another heating system question
 

So my heating is not working so well. Here is the deal. With the fan off A bit of heat comes through the 2 center vents. Even when the slider in the middle is all the way up (closed). If I want heat it works great. But it wont flow fresh air from out side. I also can not get flow up out of the front defogger vents. If I close the main flow vent some of the air is forced up but only out of the defogger right above the center vents. I dont know if the foot vents work mostly because with the windows closed the car heats up enough.

The AC does nothing, I know it needs a recharge but I dont want to do that with this hot air issue.

Now I know there is some vacuum control here but how does it work. I have sifted through the manuals but find them a bit tough to understand.

I am also not sure if those sliders on the heater unit do any thing. I know they are electric unlike the cable ones on my 911. What do they control and how can I check them.

Any suggestions on places to start looking.

Regards
Dave