I'm in need of some more help. I have looked through the forum quite a bit and can't find anyone else with this issue. The problem is that when the HVAC is set to heat no air blows out of the vents, only through the floor and defrost. The air that does blow through the floor and defrost is hot though.

If I change to the vent setting air will blow through the vents at the various speeds both cold and hot depending on what I sent the temperature dial to. The A/C also blows through the vents just fine.

What might be causing the lack of air through the vents when set to heater?

 

That's normal if you select heat; the majority of air flow exits on the floor and a slight amount from the defroster vents. If you select defrost, the majority of air flow exits the defroster vents and a slight amount to the floor. If you select bi-level, air flow exits the dash vents and the floor. AC & Max AC should exit only through the dash vents.

 

This is the problem with having not driven my blazer much for the past couple of years. I'm used to my Neon where when if it is set to heater hot air blows through the vents. In the blazer the only way to get hot air through the vents is to set it to vent with the temperature on hot. Thanks for answering such an obvious question.

There is a vent below the glove box and the steering column, what purpose do these serve? No setting results in any air being blown out of them.

 

They are connected to the dash vents, or should be. If the dash has been apart, they may not have been re-connected. There might or might not be a control at the vents to shut them off. Typically they can barely blow out a match when they're open

 

Good to know, I don't think I will worry about it then. Now that I know how to controls are supposed to work I know that flushing out the heater core a while back fixed my heat issues.

 

I also do not get anything out of my front vents either. Air comes out the top and the bottom but nothing out the front.