my heat works for the feet/windshield, but not the vents??

[E36M3wantedinNY]

and yes, I have the center vent on red (hot), with both passenger and driver climate control dials set to hot, with the ac off. However, the air coming out of the center and side vents is "warm", whereas the air to the feet and the windshield is hot. any ideas why?

is there a temp sensor for the vents that might have gone bad?

thanks

[EMMM TREE]

i have the exact same problem, wats goin on?

[E36M3wantedinNY]

i have the exact same problem, wats goin on?

at first i thought it might be normal, cause if i have everything set to hot, and put the dial to "feet" or "windshield", or even in between the two it does get really hot, so the heat itself works. but if i switch it to face, or face & feet, or even face & windshield, the face part will only be warm. But the feet air and windshield air are hot.

I don't think that happens with the ac though. I'm pretty sure the ac comes out about the same temp no matter where it's venting through. However, in other cars, like my audi a4 and honda accord, I can have the ac on, and still have the heat on. This gives me hot, dry air. But if I have the ac on in this car, the air will not come out hot - so i can't use the ac to get the moisture out of the air. How is it that bmw hvac design is worse than honda's.

[tdwyatt]

at first i thought it might be normal, cause if i have everything set to hot, and put the dial to "feet" or "windshield", or even in between the two it does get really hot, so the heat itself works. but if i switch it to face, or face & feet, or even face & windshield, the face part will only be warm. But the feet air and windshield air are hot...There are a pair of distribution motors that control flaps for heat distribution inside the vents/ductworks, one on each side of the heater box, if they go bad, or the switching for them goes bad, or the connections go bad, the heat will not work through the midlevel vents (or they could freeze in this postion and not work for the windshield vents, etc. There are three of them to check, two on the left side, one on the right side fo the heater box.

Could be the switch that actuates them, or it could be the wiring or the motors, even the flaps inside the vents if they become stuck. Check for the fuse, (I don't think they use a relay, but they might), then look for power to the electromechanical motors at their connectors, then check the switches for current when on.

One of these will prolly fix your issue.

HTH

[EMMM TREE]

thanks for ur advice, does the benlty cover this is more detail?

[tdwyatt]

thanks for ur advice, does the benlty cover this is more detail?I am sure there is a section on it in the heating/AC chapter, but the ETK or TIS may be of more use, as they will have a better diagramatic explosion of the area in question. Each motor controls a different part of the circulation pathway, check the wiring color codes in Bentley for the different switches and wiring to each motor, but it is pretty self-apparent once you start looking at the area.

HTH

:pullover

[lkstaack]

I need to bring this back from the dead because my center vents do not blow hot air either. It started as an intermintent problem that got progressively worse. I get a little air from the vent, but it's not hot (a little warm). I e-mailed Mike Miller from Roundel, but he didn't know either. Has anyone with this problem got it fixed? If so, how?

<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p>I have completely removed the dash to ID the problem. It is scary (see pic). I see that the manually operated cable and vent arm that controls the temp are working properly (see blue cable). Of course, I still can't see the operation of the flap that directs airflow because it's towards the firewall portion of the box. I also see that there are electrically operated flap (see pic with silver actuator) that controls the air from the airbox to the center vent.</o:p>
<o:p></o:p>
<o:p>I think that it is possible that the problem lies with the electrical actuator because that would account for the reduced flow to the center vent. However, I don't want to replace the actuator, put this mess back togeather, and find that it didn't fix it. </o:p>
<o:p></o:p>
<o:p>Has anyone successfully disassembled their heater box? I'm afraid that I will have to disconnect the heater and AC tubes at the firewall in order to do it. Does anyone with this type of experience have any advice?</o:p>

[HBpredhunter]

at first i thought it might be normal, cause if i have everything set to hot, and put the dial to "feet" or "windshield", or even in between the two it does get really hot, so the heat itself works. but if i switch it to face, or face & feet, or even face & windshield, the face part will only be warm. But the feet air and windshield air are hot.
I don't think that happens with the ac though. I'm pretty sure the ac comes out about the same temp no matter where it's venting through. However, in other cars, like my audi a4 and honda accord, I can have the ac on, and still have the heat on. This gives me hot, dry air. But if I have the ac on in this car, the air will not come out hot - so i can't use the ac to get the moisture out of the air. How is it that bmw hvac design is worse than honda's.

its not, your is not working right.
i am using my heater like that right now during the rainy season... ac on with heat.. the heat will overcome the cold, and dehydrate the air making a perfect defogger, while still keeping you warm