Say I want heat to come out both my bottom and top vents. Now naturally there are only 3 heat options on the firebird: Top vents, bottom and defrost. But there is a dual Top vent + bottom vent selection but it has the blue coloring meaning a/c. Now if I turn my selector to the mixed top/bottom vent one and have the temperature selection all the way to the heat is the A/c still going to run since the selecter is blue and technically not a heat setting, even though when I do it heat comes out both vents?? I have always wondered this in both my firebirds and finally go to asking.

 

you should hear or feel the ac compressor kick in if it does

 

The compressor will run. That is often referred to as "bi-level" mode. The conditioned air will then pass through the heater core if you have the temp **** at a warm setting.

 

Hmmm thats what I wanted to know..thanks! Now why the heck isn't there just a setting to have heat go through both is beyond me...