04 Explorer Heater Controls not working properly

[reglalach]

My 2004 Explorer's heater control seems to be malfunctioning. The floor setting (or combination) does not seem to blow adequately on the floor. The amount of heat being produced seems all right, I just can't seem to direct it to the desired locations. Living in Saskatchewan, this poses a problem in the winter as our feet tend to freeze while our upper bodies are toasty.
Anyone have any ideas as to what may need to be repaired to solve this problem?

 

[BrooklynBay]

Welcome to this forum! It might have a broken vacuum line.

 

[TheJackal]

Yeah, vacuum leak sounds like it to me, I've had this issue in another car of mine.

 

[reglalach]

Vacuum leak likely the culprit

A broken vacuum line or dislocated one sounds like it could be the cause all right. And it probably explains the whistle under acceleration, wouldn't it?