[dangerus_car]

see attached picture

I try sliding it to hot and cold, but i don't feel any difference, still feeling cold AC air.

so how do i know if it works or not?

Thanks.

[Psi5]

I think you answered your own question. Make sure the air is directed to the top vents and if it is, the dial should adjust the temperature warmer even if the AC is cranked.

[dangerus_car]

but when i slide it to warm temp, i don't feel warm air, still same cold AC air... that's why i m confused even after reading the manual

[Zheez]

I leave my AC on full auto mode and there is definitely a difference in the top vents when adjusting the dial. It should be fairly obvious.

Wonder if the trim has been taken off for whatever reason and the electrical connector for it hasn’t been plugged back in

[alohasurftoad]

the slider is mixing in warm air to the cold a/c air.

it is an additional(manual) way to change the selected temperature slightly, without changing what you have set electronically. not sure why bmw put it there, since you can set whatever temp you desire.

maybe if you have the AC off and slide it to full warm for heat during winter
.

[JoHnMuir]

Originally Posted by alohasurftoad

the slider is mixing in warm air to the cold a/c air.

it is an additional(manual) way to change the selected temperature slightly, without changing what you have set electronically. not sure why bmw put it there, since you can set whatever temp you desire.

Probably because Germans are superstitious about cold air giving them illness.

[Abzynthe]

All it is is a small piece of metal behind the vents that heat up slightly. It's not an instant change, it needs to heat up, but as previously mentioned, it's not a huge difference. It just takes the chill off the A/C

[HighlandPete]

Originally Posted by Abzynthe

All it is is a small piece of metal behind the vents that heat up slightly. It's not an instant change, it needs to heat up, but as previously mentioned, it's not a huge difference. It just takes the chill off the A/C

How much it changes the face level vent temperature depends on the ambient temperature and CC temperature settings.

Say you are driving in an ambient temperature of 10C and CC set to 20C. Turn to blue and it will definitely be cold. To red, and it will add warm to hot air. Mid position will be blended, to be similar to the rest of the cabin heating.

Driving in high ambient temperatures, and CC set to cool, the face vents will cool as we have a low temperature target. How we use Auto temperatures, can also change the output range.

Remember it can change as you drive, as it also senses demand towards target settings. Driver and passenger settings can also have subtle differences. In my experience the driver has priority for its function.

All BMW models I've owned (or driven) face level air stratification works perfectly, same in each example. Great feature, tuneable to personal preference.

[HighlandPete]

Originally Posted by alohasurftoad

maybe if you have the AC off and slide it to full warm for heat during winter

Works with, or without AC function. Is more limited for cooling without AC.

In my experience if set to cold, will not blow cold while cabin temperature is wide off the target temperature. As the cabin warns, closes towards the target settings, the face flow starts blowing cold. Clever stuff, as you don't need to keep playing with the thumbwheel control.

[HighlandPete]

Originally Posted by dangerus_car

see attached picture

I try sliding it to hot and cold, but i don't feel any difference, still feeling cold AC air.

so how do i know if it works or not?

What sort of temperatures are you working with? (Ambient and Climate Control settings).

[Wires]

Originally Posted by dangerus_car

but when i slide it to warm temp, i don't feel warm air, still same cold AC air... that's why i m confused even after reading the manual

It's not really a hot/cold. It changes how aggressive the HVAC kicks on. If you have it on "blue" then you tend to get it engaging the AC more pre-emptively with more flow. On "red" it lags more with less flow.

You really notice if you are driving and you get sun and then cloud cover. On "blue" you will get a lot more cold out of the vents since it's aggressively trying to maintain your set temperature.

[Onizukachan]

You’ll notice it in the winter!

And when it is 104-110 out you can tell it is not as cold.

[dangerus_car]

so if i slide it to red, for example, with AC on, how long do I have to wait until the warm air kicks in mixed with cold air AC? It's not instant, right?

[Wires]

Originally Posted by dangerus_car

so if i slide it to red, for example, with AC on, how long do I have to wait until the warm air kicks in mixed with cold air AC? It's not instant, right?

You need to re-read my post #11. There is no "warm air mixed with cold", it's purely a HVAC "aggressiveness adjustment".

[alohasurftoad]

Originally Posted by Wires

You need to re-read my post #11. There is no "warm air mixed with cold", it's purely a HVAC "aggressiveness adjustment".

thanks for clarifying this. i thought it worked like an "old school" heater vent control.

for years, i felt my AC "coldness" was substandard. i only recently noticed the dial itself and it wasn't to the full blue side. that's what i get for not RTFM

[HighlandPete]

Originally Posted by dangerus_car

so if i slide it to red, for example, with AC on, how long do I have to wait until the warm air kicks in mixed with cold air AC? It's not instant, right?

If it is compatible with the settings it should turn warm within seconds. It is blending hot and cold air.

What temperatures are you working with, ambient and HVAC settings?

[HighlandPete]

Originally Posted by Wires

You need to re-read my post #11. There is no "warm air mixed with cold", it's purely a HVAC "aggressiveness adjustment".

I think you are mixing functions, the thumbwheel is not an intensity setting. The thumbwheel is a 'blender' for face vent air stratification.

Typical technical description...

Front Stratification Adjustment Thumbwheel
The thumbwheel signal is wired directly to the IHKA control unit as an analog/varying voltage signal. The IHKA panel sends the specific position signal to the front mixing flap motor via the LIN bus.

[dangerus_car]

i tried again today, adjust all the way to auto and 60 F. then set the wheel to HOT.

i feel HOT and COLD setting the same, nothing changed...

and yes, the plug is connected at the back, because the emergency blinker and central lock works

[SW6Steve]

I find it's best use is during the winter, I get a cool flow from the top vents to aid drowsiness when the heat is on and up to temperature. I run auto all year.

[HighlandPete]

Originally Posted by dangerus_car

i tried again today, adjust all the way to auto and 60 F. then set the wheel to HOT.

i feel HOT and COLD setting the same, nothing changed...

and yes, the plug is connected at the back, because the emergency blinker and central lock works

If I'm reading this correct, you have the HVAC system running the lowest 'unregulated' temperature setting and are trying for heat from the face level vents at the same time? My understanding, there is a conflict of commands, as the HVAC is trying for the lowest target temperature possible.

What happens when you select a temperature 65 - 70 F, then try the hot to cold range?

[HighlandPete]

Originally Posted by SW6Steve

I find it's best use is during the winter, I get a cool flow from the top vents to aid drowsiness when the heat is on and up to temperature. I run auto all year.

Similar here. Yes, works well in winter to mid range temperatures.

[Wires]

Originally Posted by HighlandPete

I think you are mixing functions, the thumbwheel is not an intensity setting. The thumbwheel is a 'blender' for face vent air stratification.

Typical technical description...

Mine doesn't work like that description (at least from my experience). But heh, results may vary!