1989 TC: Heat blows hot, A/C blows Cold.....but only thru the A/C vents.

[sposey7]

Hi there.

As the title states, heat is hot, a/c is cold. The problem is no matter where I put the selector, the air blows thru the A/C vents. I cannot make it go to Mix, Defrost, or Floor.

I've connected the clear vacuum tube to the door actuator. When it's connected it blows cold, and when it's not, it blows hot.

I want to be able to at least control the airflow to the defrosters, floor, vent, etc.

Where do I need to begin?

Thank you in advance.

 

[msasteel]

The TC uses vacuum to control that actuator, so it would appear that the lever that controls the porting of the vacuum to the that door is either plugged (unlikely) or it is leaking too much to transfer the door. You don't mention the temperature control through the vents. Can you control the temperature through those vents? If so, the temperature blending is working, but the porting door is not. the door you are saying blows cold then hot, is the blending door, not the door that ports the air to the appropriate outlets. There is another actuator that does this. I would make sure that guy works first, then go to the vacuum valves on that are part of the lever assembly for the floor, etc. You can test the vacuum valve assembly by connecting the vac as it should be and seeing if the vacuum will go to other outlets as you move through the detents - the vents, the mix, the floor and the two defrost positions. Hope that helps and is not too late. Good luck!

 

[sposey7]

I can't control the temperature at all. Right now I have the clear vacuum tube disconnected so it blows hot air since it's winter.

I can't control where the air goes (defroster vents, heater vents or A/C vents) It seems to go out all of them. I closed off the A/C vents so the air goes out the defroster and heater as much as possible.

I think I'm having issues with both the temp blending door, and the the doors that divert the air.