My Heat and AC air only blows trough the defogger, nothing comes out trough the Vents or the Feet. Any solutions I have a Ford Explore XLT 97.??

I recently had this same problem after having some work done on my 1999 Explorer. Took it back to the garage, they said a "vacuum hose" had been left unconnected. Connected the hose, now the air blows through the correct vents...but...the heat doesnt seem to ever get really warm???