Control problem, blend door not working are the places to start
check the temp guage if low change the thermostat
If the air vents of the Chevy trailblazer 2004 are not blowing air, have the fuel pump checked.
The air of your Chevy trailblazer 2004 blow out of the front vents when the air conditioner is on because the air condition is faulty and it needs repair.
air want blow out vents
The blend door actuator may not be working.
The controls that direct the air flow to the defroster, to the vents and to the floor are vacuum operated. You may have a vacuum leak causing your problem. Check under the hood for broken, cracked, disconnected vacuum lines.
I've got a better question, why is this question in the Chevy venture forum ?
Check the 96 Blazer for any vacuum leaks in the system. A vacuum leak can cause the air flow to only come out of the heat vent.
The HTR RR switch in a Kia Sedona determines which air vents the air is blown through from the rear heating. When it is pushed in, the lower vents blow hot air, and when it is not pushed, the roof vents blow cold air.
Possible blockage in the rear air units expansion valve. I just replaced mine for the same reason.
why my floor air comes on when the setting is at panel air on 2004 Chevy blazer
Check Antifreeze level..make sure there are no leaks under the vehicle.