Heater control knob stops halfway for heat Jeep Cherokee Sport

[indycalgary]

i flushed the system at the firewall and it ran out pretty clean..... but the control knob will not go to the full heat position as if something is plugged/stopping it from going to full heat? in the winter is warm but not hot, thermostat is new... but no matter.... why is the heater knob going to full heat? Couldn't  find a response directly relating to this problem here.

[jkrubi]

follow the control cable from under the dash to the rheostat/temp control valve and make sure that it is not jamming up,  and going full hot to full cold ( by hand not knob).  And do the adjustment to make it operate correctly. 

[JJonesee]

This may sound like a stretch, but what year?

If its the rotary switches odds are the actual knob has broken.  They like to split along the female D shaft and not function.