Re: ED Falcon climate control
You should have two lines coming from through the firewall.
Green....to heater tap.
Black...to manifold vacuum.
they will be paired coming through the same hole in the firewall.
If the vacuum hose has come off..as it sounds like it has, simply moving it about its length will locate its proper mount point.
If this is off if your ears are good enough you will hear the suction from the engine whilst running....it will also degenrate your fuel consumption figure.