A/C Help

Can anyone help me out, my 1992 S-10 Blazer A/C comes out everywhere except were its suppose to come out(dash vent) I checked every vacuum line I can fine and it makes no difference. Can someone tell me if I can bypass all that vacuum stuff and just make the dash vents work?
Thanks
Joe

PS Oldmaster said to look at check valve, whats the check valve look like?

I replaced the check vavle and almost all the vacuum line, air comes out of floor vent and defroster vent, no mater were I put the lever it will not come out of dash vents. HELP it my wifes car and she is hot.
Thanks
Joe

Can someone tell me if I can bypass all that vacuum stuff and just make the dash vents work?
Thanks
Joe