What's with the "Auto" A/C?

leemj84 · 07-03-2019, 08:02 PM

Hey guys, not sure if this is an issue with my car or a quirk with f30s...

When I have the AC on the auto setting, I expect the car to realize it's too hot and turn up the AC and fan speed, and when it gets to the target temp, to turn down the fan speed. However, I noticed that the fan speed does not change regardless of how low I put the temperature and I have to turn up the fan speed manually. Doesn't that defeat the purpose of the auto setting?

Is this an issue that I need to have the dealer check out or is this a quirk that I need to learn to live with?

Thanks!

paimon.soror · 07-03-2019, 09:20 PM

I don't believe the fan speed changes (or the "intensity" level as it is called in auto). Instead it will regulate the air temp, compressor, and where it is blowing from to make sure it doesn't get too hot or cold based on your selected temp.

I know my wife's cx5 changes the air speed based on the temp.

HighlandPete · 07-04-2019, 03:53 AM

Quote:

Originally Posted by leemj84

Hey guys, not sure if this is an issue with my car or a quirk with f30s...

When I have the AC on the auto setting, I expect the car to realize it's too hot and turn up the AC and fan speed, and when it gets to the target temp, to turn down the fan speed. However, I noticed that the fan speed does not change regardless of how low I put the temperature and I have to turn up the fan speed manually. Doesn't that defeat the purpose of the auto setting?

Is this an issue that I need to have the dealer check out or is this a quirk that I need to learn to live with?

Thanks!

Fan speed will change on demand, in Auto mode. The 'range' of fan speed is simply controlled by the intensity level you set.

What intensity are you running? What happens when you change the intensity in Auto mode?

For example, if you are running the lowest intensity, when there is high demand the fan will speed up but only to about mid range, then cut back as target temperature is reached. Higher intensity, will speed much more on demand, then cut back as temperature is achieved.

jamesdak · 07-04-2019, 07:24 AM

I've been wondering about this. It's been the one thing about the car that doesn't impress me. Any other vehicle I've had with an auto function controlled fan speed regardless of how it was manually set. I think BMW missed the boat on this one.

HighlandPete · 07-04-2019, 07:37 AM

Quote:

Originally Posted by jamesdak

I've been wondering about this. It's been the one thing about the car that doesn't impress me. Any other vehicle I've had with an auto function controlled fan speed regardless of how it was manually set. I think BMW missed the boat on this one.

BMW used to have the more basic system in older models. Intensity level options were introduced years ago. Has been used in 3-series from the E90, available in iDrive, not on the display panel as the F30 models.

It is an advanced feature, giving users the choice of air flow volumes.

The Kurgan · 07-04-2019, 07:37 AM

It depends. When you first start your car, it goes into full auto mode and regulates fan speed. I noticed that when the car gets to set temperature, there is control over fan speed. Its a bit odd, but "auto" definitely works well, so I live with it.

Billfitz · 07-04-2019, 07:44 AM

Quote:

Originally Posted by HighlandPete

Fan speed will change on demand, in Auto mode. The 'range' of fan speed is simply controlled by the intensity level you set.

+1. The speed indicator doesn't show any change in the fan speed, because that's not what the indicator is for. In auto mode it shows the speed range that the fan is operating within. If the system was truly 'automatic' and there was no way to adjust the speed range then there would be complaints about that. To paraphrase Abraham Lincoln, 'you can't make all of the people happy all of the time'.

HighlandPete · 07-04-2019, 08:55 AM

Quote:

Originally Posted by Billfitz

+1. The speed indicator doesn't show any change in the fan speed, because that's not what the indicator is for. In auto mode it shows the speed range that the fan is operating within. If the system was truly 'automatic' and there was no way to adjust the speed range then there would be complaints about that. To paraphrase Abraham Lincoln, 'you can't make all of the people happy all of the time'.

Agree.

Does appear the BMW Climate Control is too complex for many users. Either little or no understanding of the intensity feature, and/or the face level air flow 'thumbwheel' feature.

celsdogg · 07-04-2019, 09:10 AM

in auto mode, the driver sets the max fan speed. it'll run at the speed the driver sets then ramp down when temp is reached.

HighlandPete · 07-04-2019, 09:18 AM

Quote:

Originally Posted by celsdogg

in auto mode, the driver sets the max fan speed. it'll run at the speed the driver sets then ramp down when temp is reached.

I assume by that comment you mean the driver sets the intensity level.

leemj84 · 07-04-2019, 09:34 AM

Okay, I guess my issue is that I didn't have a clear understanding and definition between intensity level and Dan speed.

So I set the intensity, but will the intensity change with the temp in the car? If I put it at the highest intensity and set auto at 65deg, will it reduce the intensity once it gets down to 65 deg?

COKen · 07-04-2019, 10:18 AM

Quote:

Originally Posted by leemj84

Okay, I guess my issue is that I didn't have a clear understanding and definition between intensity level and Dan speed.

So I set the intensity, but will the intensity change with the temp in the car? If I put it at the highest intensity and set auto at 65deg, will it reduce the intensity once it gets down to 65 deg?

Yes. Just think of it that you are setting the max fan speed and the auto function will change the fan speed between low and your max speed as needed.

HighlandPete · 07-04-2019, 10:22 AM

Quote:

Originally Posted by leemj84

Okay, I guess my issue is that I didn't have a clear understanding and definition between intensity level and Dan speed.

So I set the intensity, but will the intensity change with the temp in the car? If I put it at the highest intensity and set auto at 65deg, will it reduce the intensity once it gets down to 65 deg?

Intensity is simply a setting to get the kind of air flows a user prefers.

I personally run a low intensity setting. I don't want lots of air blowing at any temperature. The system still speeds up when the demand is high, say to heat or cool the cabin, but quickly settles to a low background air flow.

Other's prefer a lot more air. Simply set a higher intensity. You'll have more air flow in the heating and cooling phases, and will settle to a lower flow, but more general airflow than a low setting.

Intensity is a range of airflow.

azuritschwarz · 07-04-2019, 11:09 AM

Somewhat unrelated, but since we're on this topic of auto climate control; my girlfriend has a 2012 Audi A4, & whenever she takes it in for service, the techs always joke with her about not leaving her fans on auto, for a number of reasons. Obviously because it's easier, but they also mentioned that it helps the car warm up quicker by not leeching heat from the engine until it starts to circulate itself.

Sure enough her car warms up nearly 2x as fast when on Auto vs a regular temp setting. It does not run the fans at all for the first few minutes of driving.

I have tried to replicate this in both my F32 440i & my E90 335i, & have noticed no difference in how quickly the engine warms up. It runs the fans at whatever speed deemed necessary by Auto, rather than stopping functionality until warm up begins.

Is this just a simple difference between BMW & Audi & how they're setup, or should I be noticing a quicker warm up when on Auto?

HighlandPete · 07-04-2019, 11:24 AM

Quote:

Originally Posted by yeg440i

Is this just a simple difference between BMW & Audi & how they're setup, or should I be noticing a quicker warm up when on Auto?

BMW state the car heats and cools (achieves desired temperature) as quickly as possible in Auto mode.

BigJack75 · 07-04-2019, 11:30 AM

My ac is normally set to 75 degrees on auto. If I get in the car after sitting in the hot sun the interior is 100 degrees. I need to manual press the max ac which puts the temp to 60 degrees and fan at full blast. After usually about 5 minutes the car is cooled down enough and I can put the fan on a lower setting but keep the temp at 60. If I am driving for an extended period of time ( hour or more) I can switch the ac back to auto and am cooled. The point is I have to regulate it myself. The ac is not bad on this car but other cars were better.

MmmmmM2 · 07-04-2019, 11:32 AM

I never use auto A/C. I can regulate my fan speed manually.

azuritschwarz · 07-04-2019, 11:37 AM

Quote:

Originally Posted by HighlandPete

Quote:

Originally Posted by yeg440i

Is this just a simple difference between BMW & Audi & how they're setup, or should I be noticing a quicker warm up when on Auto?

BMW state the car heats and cools (achieves desired temperature) as quickly as possible in Auto mode.

Thanks for the reply. I know it will get to the desired temp as soon as possible, I was more so just curious about warmup behaviour. On the A4, it warms up the engine twice as fast on Auto as it does even with climate control off. It cuts the HVAC off completely until the oil temperature gets up to about 40-50 degrees Celsius, & only then it starts blowing air.

On our BMW's however, I have not noticed this. Seems like it places priority on cabin temperature rather than engine temperature. It may be largely irrelevant, but it was something I noticed & was curious about.

Zanity · 07-04-2019, 11:50 AM

Quote:

Originally Posted by F30ZHP

I never use auto A/C. I can regulate my fan speed manually.

same here, only issue with that is I've seen button logos wear out quicker because we use manual HVAC control. BMW has really been cutting cost on the F series. The engine start button logo especially will wear out over usage.

HighlandPete · 07-04-2019, 05:40 PM

Quote:

Originally Posted by yeg440i

Thanks for the reply. I know it will get to the desired temp as soon as possible, I was more so just curious about warmup behaviour. On the A4, it warms up the engine twice as fast on Auto as it does even with climate control off. It cuts the HVAC off completely until the oil temperature gets up to about 40-50 degrees Celsius, & only then it starts blowing air.

On our BMW's however, I have not noticed this. Seems like it places priority on cabin temperature rather than engine temperature. It may be largely irrelevant, but it was something I noticed & was curious about.

When I said as fast as possible, that does include the Heat Management which involves the engine coolant management and interaction between the DME and IHKA control unit. Wiring diagrams support the DME/IHKA links.

When you read through the BMW Climate Control Workbooks, quite a bit of the content is on the engine coolant management. So interlinked with present systems. BMW don't spell out every detail, so whether Auto mode is more efficient than manual settings, is impossible to tell.

I know in my current F11 5-series, there are delays in heat output to the HVAC, particularly noticeable in cooler weather. It does appear the engine temperature has some priority, much more so than the days of my E39 where heat to the HVAC system was much faster.

BMW diesel engine HVAC performance (and apparent efficiency) is masked by the fact there is an electric PTC heating element in the system. It produces heat ahead of the engine coolant giving out any heat whatsoever.

MmmmmM2 · 07-04-2019, 07:04 PM

Quote:

Originally Posted by Zanity

same here, only issue with that is I've seen button logos wear out quicker because we use manual HVAC control. BMW has really been cutting cost on the F series. The engine start button logo especially will wear out over usage.

The engine start button wore out on my E92 as well.

jamesdak · 07-04-2019, 07:52 PM

I guess it seems strange to me that I have to control the max speed of the fan when in Auto mode. That is different than every other car I've owned and I was not aware of it. It does explain why I'd have the temp set to 60 and still be hot on the 30 minute drive home. Now I'll just leave the fan at max speed and let it do it's thing. Just one extra step over my other cars.

On the flip side I love how the cruise control brakes, that's a first for me too. I can drive down the steep mountain passes here with the cruise control set and never touch the brakes, awesome!

07-03-2019, 08:02 PM	#1
leemj84 leemj84 32 Rep 57 Posts Drives: F30 340i xDrive Join Date: Mar 2019 Location: Iowa iTrader: (0) Garage List 2016 BMW 340i xdrive [0.00]	What's with the "Auto" A/C? Hey guys, not sure if this is an issue with my car or a quirk with f30s... When I have the AC on the auto setting, I expect the car to realize it's too hot and turn up the AC and fan speed, and when it gets to the target temp, to turn down the fan speed. However, I noticed that the fan speed does not change regardless of how low I put the temperature and I have to turn up the fan speed manually. Doesn't that defeat the purpose of the auto setting? Is this an issue that I need to have the dealer check out or is this a quirk that I need to learn to live with? Thanks!
	Appreciate 0 Tweet Quote

07-03-2019, 09:20 PM	#2
paimon.soror Captain 631 Rep 969 Posts Drives: 2016 F36 435x MSport Join Date: Oct 2017 Location: Hartford, CT iTrader: (3) Garage List 2016 BMW 435xi GC [6.00]	I don't believe the fan speed changes (or the "intensity" level as it is called in auto). Instead it will regulate the air temp, compressor, and where it is blowing from to make sure it doesn't get too hot or cold based on your selected temp. I know my wife's cx5 changes the air speed based on the temp.
	Appreciate 0 Quote

07-04-2019, 07:24 AM	#4
jamesdak New Member 17 Rep 29 Posts Drives: 340i with M Sport packages! Join Date: May 2019 Location: Utah iTrader: (0)	I've been wondering about this. It's been the one thing about the car that doesn't impress me. Any other vehicle I've had with an auto function controlled fan speed regardless of how it was manually set. I think BMW missed the boat on this one.
	Appreciate 0 Quote

07-04-2019, 07:37 AM	#6
The Kurgan Private 28 Rep 82 Posts Drives: 2012 BMW 328i Luxury Line RWD Join Date: Jun 2019 Location: Hamilton, Ontario, Canada iTrader: (0)	It depends. When you first start your car, it goes into full auto mode and regulates fan speed. I noticed that when the car gets to set temperature, there is control over fan speed. Its a bit odd, but "auto" definitely works well, so I live with it.
	Appreciate 0 Quote

07-04-2019, 09:10 AM	#9
celsdogg E4 Mafia 329 Rep 418 Posts Drives: E30, E36/5, E46x2, F22, F30 Join Date: Apr 2018 Location: MD iTrader: (0)	in auto mode, the driver sets the max fan speed. it'll run at the speed the driver sets then ramp down when temp is reached. __________________ Squad - '90 E30 325i MT (225k) \| '98 E36/5 318ti MT (153k) \| '03 E46 325i MT (152k) \| '04 E46 330xi MT (198k) \| '15 F22 M235i MT (60k) \| '15 F30 335i MT (80k) KIA - '91 E30 325i AT (146k) \| '02 E46 325i MT (212k) Bring back the purple M stripe
	Appreciate 0 Quote

07-04-2019, 09:34 AM	#11
leemj84 leemj84 32 Rep 57 Posts Drives: F30 340i xDrive Join Date: Mar 2019 Location: Iowa iTrader: (0) Garage List 2016 BMW 340i xdrive [0.00]	Okay, I guess my issue is that I didn't have a clear understanding and definition between intensity level and Dan speed. So I set the intensity, but will the intensity change with the temp in the car? If I put it at the highest intensity and set auto at 65deg, will it reduce the intensity once it gets down to 65 deg?
	Appreciate 0 Quote

07-04-2019, 11:09 AM	#14
azuritschwarz First Lieutenant 348 Rep 352 Posts Drives: 2007 E90 335i, 2016 F80 M3 Join Date: Nov 2017 Location: Edmonton, AB iTrader: (0) Garage List 2017 BMW 440i Coupe [0.00] 2006 BMW 330i [0.00] 2007 BMW 335i [0.00] 2016 BMW M3 [0.00]	Somewhat unrelated, but since we're on this topic of auto climate control; my girlfriend has a 2012 Audi A4, & whenever she takes it in for service, the techs always joke with her about not leaving her fans on auto, for a number of reasons. Obviously because it's easier, but they also mentioned that it helps the car warm up quicker by not leeching heat from the engine until it starts to circulate itself. Sure enough her car warms up nearly 2x as fast when on Auto vs a regular temp setting. It does not run the fans at all for the first few minutes of driving. I have tried to replicate this in both my F32 440i & my E90 335i, & have noticed no difference in how quickly the engine warms up. It runs the fans at whatever speed deemed necessary by Auto, rather than stopping functionality until warm up begins. Is this just a simple difference between BMW & Audi & how they're setup, or should I be noticing a quicker warm up when on Auto? __________________ 2016 F80 M3 6MT Azurite Black/Sakhir Orange Full Leather 2007 E90 335i 6MT Black Sapphire Metallic/Terra Brown Leather 2017 F32 440i xDrive 6MT Alpine White/Coral Red Leather (SOLD) 2006 E90 330i 6MT Arctic Metallic/Lemon White Leather (SOLD)
	Appreciate 0 Quote

07-04-2019, 11:30 AM	#16
BigJack75 Lieutenant 203 Rep 533 Posts Drives: M5 Dream Car Join Date: Aug 2018 Location: Right Here iTrader: (0)	My ac is normally set to 75 degrees on auto. If I get in the car after sitting in the hot sun the interior is 100 degrees. I need to manual press the max ac which puts the temp to 60 degrees and fan at full blast. After usually about 5 minutes the car is cooled down enough and I can put the fan on a lower setting but keep the temp at 60. If I am driving for an extended period of time ( hour or more) I can switch the ac back to auto and am cooled. The point is I have to regulate it myself. The ac is not bad on this car but other cars were better. __________________ 435i GC
	Appreciate 0 Quote

07-04-2019, 11:32 AM	#17
MmmmmM2 Colonel 2599 Rep 2,434 Posts Drives: 2021 M2C Join Date: Mar 2019 Location: Claremont, CA iTrader: (0) Garage List 2016 Mazda CX-5 [0.00] 2021 BMW M2C [0.00]	I never use auto A/C. I can regulate my fan speed manually.
	Appreciate 0 Quote

07-04-2019, 07:52 PM	#22
jamesdak New Member 17 Rep 29 Posts Drives: 340i with M Sport packages! Join Date: May 2019 Location: Utah iTrader: (0)	I guess it seems strange to me that I have to control the max speed of the fan when in Auto mode. That is different than every other car I've owned and I was not aware of it. It does explain why I'd have the temp set to 60 and still be hot on the 30 minute drive home. Now I'll just leave the fan at max speed and let it do it's thing. Just one extra step over my other cars. On the flip side I love how the cruise control brakes, that's a first for me too. I can drive down the steep mountain passes here with the cruise control set and never touch the brakes, awesome!
	Appreciate 0 Quote