Vent control problems?

My S10 does not have any air at the bottom heater vent. When turned to that position the air comes out of the defrost vents. The heat can be changed from defrost to the the vents that come out at face level (the ones commnonly used for air conditioning). The other symptom present is that when changing from position to position it is very slow. Probably takes 5-8 seconds to fully change from face to defrost or the other direction.

The heat is great. Very warm so no problems there.

What are the possible causes and solutions to this issue?

I have a 2002 with the same problem. I believe the door is not moving. They used to be vacuum operated, but I think these may be driven by little motors as you don't hear that tell-tale whoosh from the vacuum operated ones. If you've sense rectified your problem, would you please let me know what it was?
Thanks,
mike

When my heater is on it works vine but the floor vents do not work at all. Could you please give me a suggestion as what is the problem and how to repair.

My heater will only blow from the top vent(defrost) when the switch is in top middle or floor selector position. It stays in the defrost mode. It will switch to the middle air vents when it is in that position, but will not blow out of the floor vent in any position.

My a/c only blows out of the floor vent. No matter where I put the selector switch it will not give me a/c through upper vent.

My 96 S 10 I Noticed Today That The AC Is Not Comming Out THe Dash Vents But Only Out From The Defogger Vent On Top Of The Dash And The Vents Under The Dash Any Ideas

Sound like the vent door stuck open.

I recently purchased a chevy s10 with high mileage. Upon purchasing said vehicle the person told me the ac worked but sometimes did not blow out of the front vents just the defrost and the floor. I did testdrive the truck and found that it only blows out of the defrost and floor so far. Is this a simple fix? Where should I start?

When I turn on the A/C the cold air comes out the defrost area and the floor but not the vents. Even without the A/C on I can't get air to flow out the vents. Is there a schematic that shows where the vacuum lines are? Or, is there a switch or something that I need to fix/replace?

Thanks mastertechtim, I can look on line and find were each of these items are located. The nice thing is to know it is a vaccum line. Thanks for your help

My 1994 chevy s-10 leaks on the passenger side when it rains. It seems to be coming from the a/c vent under the dash that opens up when u recirculate the a/c on the passenger side.

The heater/AC on my '88 S10 Chevy Blazer blows hot/cold air well. However, when I adjust the selector to any of the AC choices, the air only blows on the floor rather than
the dash vents.

I've checked to see that the 2 vacuum hoses are connected to the heater/AC diaphragm on the floor. Maybe the other ends aren't connected.

Questions

1. Could this be the reason that the baffles don't adjust to bring the air to the dash vents?

2. If so, is there a diagram showing their location on the other side of the firewall?

3. Is there a handy "how to" cheat sheet to disassemble/reassemble the heating/AC system if it turns out that the diaphragm is bad?

My Chilton manual is lacking any information on how to troubleshoot this problem,

Thanks a million,

Jbil