Hi I am having problems with my heater box.

1) Whenever I move the temp selector from cool to hot I hear a vacuum leak. But when I move it all the way to cool ( far left ) she stops.

2) air will only blow from the defrost vents. Nowhere else. Any ideas?

Thanks All
Dennis

 

1. Sounds like the vacuum line that goes to your heater control valve is disconnected somewhere

2. Sounds like there isn't enough vacuum left after the leak in #1, for there to be enough to operate all the little doors, so they all just fall back to their "rest" position which is Defrost