No heat from center dash?

[dannysauer]

So, my heater does put out heat - but only from the dash, floor, and outer dash vents. I get no heat from the center two vents; they blow out the same volume of air as the outer ducts, but it's cold. My A/C compressor has a giant leak and isn't even hooked up, so I'm pretty sure that's not the issue. :)

Any idea what the heck's going on here?

[acefinland]

Think that's what they are supposed to do, just fresh air...

[Beach Bum]

Your recirculation flap might be stuck, partially blocking the airflow into the center ducting. I don't have a clue how it's arranged in there, but that's the only thing I can think of. Turn the car on without running the motor, hit your recirc button on the climate control and see if you can hear the motor actuate.

[dannysauer]

Recirculate does work (at least some). I guess I can accept that they're supposed to be only fresh air, but that's still weird. :)

[Ceeker]

Here is a pic of the dash layout. number 6,7,8 are cold air ducts while the others are warm.

[Ceeker]

speaking of heat. my car runs between 1/4 and 1/2 engine temp. But even at this level I still get luke warm air in the cabin. When I direct the controls to the feet and mid vents it is luke warm. When I direct the heat to the mid vents only it is noticeably warmer but not hot.

I am wondering may be the heater tap is not opening all the way? any suggestions?

thanks.

[Beach Bum]

Uh, actually, when I turn the heat on, hot air comes out of my console vents, and whatever other vents I have open. There is a problem with your ducting, somewhere. When you turn the knob over to heat, you should be getting heat, regardless of where the air is coming out.

[dannysauer]

Uh, actually, when I turn the heat on, hot air comes out of my console vents, and whatever other vents I have open. There is a problem with your ducting, somewhere. When you turn the knob over to heat, you should be getting heat, regardless of where the air is coming out.

Maybe yours is broken? :D

I dunno, but this is what I'd expect to happen. Everything else on the car is designed sanely, but having cold air blow out when the heat is on is just nuts.

[Van Westervelt]

Center is supposed to blow warm air, same as the rest of the ducts. You likely have something blocking air or a duct. Not sure if the heater core could be blocked like that...

E34s have a seperate outside air vent, e30s dont.

[dannysauer]

Center is supposed to blow warm air, same as the rest of the ducts. You likely have something blocking air or a duct. Not sure if the heater core could be blocked like that...

E34s have a seperate outside air vent, e30s dont.

The weird part is that the same volume of air comes out of the center vents as the side vents, and they blow cold air with the A/C. Well, it was cold before my AC pump blew the rear seal out ;)

Meh. Anyone want to buy a rust-free '89 325i with center cold air vents? :)

[Ceeker]

Maybe yours is broken? :D

I dunno, but this is what I'd expect to happen. Everything else on the car is designed sanely, but having cold air blow out when the heat is on is just nuts.

the most likely culprit is the heater tap not working properly. This is supposed to let the hot coolant into the heater core once the engine gets to operating temperature. Now if it is stuck partially closed the volume of water flowing into the heater core is reduced keeping the core below temp below the engine coolant temp. a weak flow will result in luke warm air. the other thing could be a partially blocked heater core itself. I usually change both the core and heater tap together.

[Yonkers320is]

what is the heater tap?
I have the same problem, luke warm air while at speed on the highway and hot air when cruising around town. I replaced thermostat (from Bavauto) heater core, coolant, hoses, pipes, etc. and the same problem.
The engine temp will be below half all the time......

[nomansland92]

Uh maybe i should replace heater tap and core also. It takes 10 minutes for me to get any warm air and if i stop at a light i get instant cold again. Any other ideas that wound cause this?

[Beach Bum]

Uh maybe i should replace heater tap and core also. It takes 10 minutes for me to get any warm air and if i stop at a light i get instant cold again. Any other ideas that wound cause this?

Air bubbles. Bleed your cooling system.

[Ceeker]

I am still stumped with this warm air BS. I just changed my thermostat, fan coupling, heater core and heater tap and even the center dash switch and finally the heater valve(put in afterward as a bulletin) which was plugged and I still get warm air. the air flow is much stronger now with all these changes.
I am still getting 1/4 on the temp reading and notice when I have the floors and mid vents going I get warm on the floors and luke warm mid vent. When I switch over to defrost it's warm but any combination with the center vent always the center is luke warm or slightly cool. If I put it only to center then it is luke warm. I bled the crap out of the system.

WTF????