Parking ventilation

[nechronics]

ok that's what I've always assumed...i was wondering if BMW conjured up some miracle with this system.

[drvai]

So the bottom line is that you can program the ventilation system to turn on at 2 different times within a 24hr period. So for example if you get out of work at 5pm, you can program the thing to turn on at 4:30 so it will have the car ventilated when you step in.

[rvacha]

Originally Posted by drvai

So the bottom line is that you can program the ventilation system to turn on at 2 different times within a 24hr period. So for example if you get out of work at 5pm, you can program the thing to turn on at 4:30 so it will have the car ventilated when you step in.

That is indeed the bottom line.

[Champagne]

This would not work as to heat up the car for us in Europe?

[rvacha]

Originally Posted by ArtPE

all batteries are kept charged to ~the same level...14.2 VDC

what I'm saying, instead of the hassle of programing times into I-Drive everytime you park the car, just let the cabin temperature controller cycle the fan when the car is off...

the way it is now, you could program it to kill the battery, and they state such in the manual

Originally Posted by ArtPE

all systems have a deadband...

say fan on at 82
run fan only
off at 78
avg is 80
repeat
this avoids the 'short cycling' you described

the ac only works with the engine running

Actually, all of my BMWs run 13.8V, not 14.2. BUT the M3 appears to be different. With the BER system the battery charge state meanders around and the charging system doesn't charge the battery full time unless the charge state is low enough that your ability to start the car is jeopardized.

The parked ventilation system is already smart enough not to run the vent fan if the battery is too low. Ditto for the Rest system, which the E9X series doesn't have. The problem with your approach - especially when married to BER - is that the fan may cycle on/off, then have to turn off hours before you get back in the car to preserve the remaining charge for starting the engine. With the timed system it is more likely to have cooled your car when you want it most - at the time you return to your car - without running your battery unnecessarily into the ground.

If you set the threshold at 82F as you propose then on a sunny day with an 85F ambient, the fan will be asked to run constantly. A better deal IMHO would theoretically be to base fan operation on temperature delta between outside temp and inside temp. BMWs unfortunately suffer from exterior temp sensor "heat soak" that makes this a tricky proposition and it still doesn't fully avoid the premature battery run down issue.

The Parked Vent fan runs nearly full tilt to get significant fresh air (i.e. cool air) into the cabin. The fan operation is clearly audible from outside the car, and the AH load on the battery is quite high

Perhaps the best compromise between utility and convenience is to be able to assign the Parked Ventilation menu to one of the customizable buttons (perhaps this is already possible?)

[southlight]

Originally Posted by lucid

There is a simpler way in the coupe: just prop the rear window panels. I am pretty sure the rest of the world does not have this option, but we will get it in the US! I use it all the time in the summer in my E46 coupe.

I don't think the rear panels are tiltable in the E92 (unlike the E46).


Best regards, south

[rvacha]

Originally Posted by Champagne

This would not work as to heat up the car for us in Europe?

No. This requires the Rest mode, which the E9X series does not support. In Rest mode the residual engine heat is used to heat the interior. I believe the criteria for entering Rest mode are

1. Ambient temp below 50F
2. An acceptable minimum charge on the battery
3. An acceptably high engine temp
4. User selection of the Rest button

Basically, even if you had the feature, there would be many situations where it would not work

[southlight]

Originally Posted by rvacha

No. This requires the Rest mode, which the E9X series does not support. In Rest mode the residual engine heat is used to heat the interior. I believe the criteria for entering Rest mode are

1. Ambient temp below 50F
2. An acceptable minimum charge on the battery
3. An acceptably high engine temp
4. User selection of the Rest button

Basically, even if you had the feature, there would be many situations where it would not work

The E9x does have this Rest mode. I think what Champagne's talking about is park heating, which is available for the E9x series as extra equipment, but not for the M3.


Best regards, south

[Champagne]

Originally Posted by rvacha

No. This requires the Rest mode, which the E9X series does not support. In Rest mode the residual engine heat is used to heat the interior. I believe the criteria for entering Rest mode are

1. Ambient temp below 50F
2. An acceptable minimum charge on the battery
3. An acceptably high engine temp
4. User selection of the Rest button

Basically, even if you had the feature, there would be many situations where it would not work

Yes, I'm well aware of Rest mode, but the problem with it is that if I go to school in the morning and want the car to be somewhat warm when I get back like 5 hours later... The rest mode wouldn't be sufficient. It only heats like you say as long as the engine is warm, and it would cool down in like 20 minutes or so when it's - degrees.

I can further develop this post with that I actually asked my dealer when ordering about "Ebersprescher"(or how it's spelled), an engine up-heater through remote control, but the response was that since it's a sports car they didn't put it in (and thank god really). I even asked about a coupé heater (which does somewhat to what I want but you have to plug in a cable into an electric outlet), and he said they could install it, but for that to be installed they would have to do some ugly drilling and so on. Thanks but no thanks really, I rather be cold for 4 minutes until it's warm.

The reason for me asking is if this function would work as a hair dryer for when it's cold outside, just interested.

[ArtPE]

all Bosch/Vario alternators will run from 13.5 to 14.5 depending on load and charge state...the battery alone ~12.5 to 13...
regardless of the actual cut-off, number it can be set...

the manual specifically says not to use twice in a row, or you will drain the battery...use it once, drive/recharge...

the problem with running on a timer is:
it wastes energy, could run when it's already cool, could run longer than requred...using the sensors would prevent this...

if it's 85 outside, and set at 82, it would NOT run under my scenario
if oat<setpoint run, otherwise no...
a differential would work also...
if the cabin exceeds oat by a given amount, then run...

Originally Posted by ArtPE

that's a stupid way of doing it...

why not just enable it and pick a set-point, say 80f
then let the exterior/interior temp sensors control it?

eg, if you enable and set it at 80f...
and the interior >80 and the oa<80 turn the fan on until interior<80...
then shut down

monitor battery voltage, if too low, auto disable

you can tell the engineers who did I-drive (the joke of the industry) came up with this scheme...
it's too complex, and not flexible...basically useless...

Originally Posted by rvacha

Actually, all of my BMWs run 13.8V, not 14.2. BUT the M3 appears to be different. With the BER system the battery charge state meanders around and the charging system doesn't charge the battery full time unless the charge state is low enough that your ability to start the car is jeopardized.

The parked ventilation system is already smart enough not to run the vent fan if the battery is too low. Ditto for the Rest system, which the E9X series doesn't have. The problem with your approach - especially when married to BER - is that the fan may cycle on/off, then have to turn off hours before you get back in the car to preserve the remaining charge for starting the engine. With the timed system it is more likely to have cooled your car when you want it most - at the time you return to your car - without running your battery unnecessarily into the ground.

If you set the threshold at 82F as you propose then on a sunny day with an 85F ambient, the fan will be asked to run constantly. A better deal IMHO would theoretically be to base fan operation on temperature delta between outside temp and inside temp. BMWs unfortunately suffer from exterior temp sensor "heat soak" that makes this a tricky proposition and it still doesn't fully avoid the premature battery run down issue.

The Parked Vent fan runs nearly full tilt to get significant fresh air (i.e. cool air) into the cabin. The fan operation is clearly audible from outside the car, and the AH load on the battery is quite high

Perhaps the best compromise between utility and convenience is to be able to assign the Parked Ventilation menu to one of the customizable buttons (perhaps this is already possible?)

[PFitto]

Originally Posted by rvacha

The parked ventilation system is already smart enough not to run the vent fan if the battery is too low. Ditto for the Rest system, which the E9X series doesn't have.

What are you talking about here??!!! All e9X have the REST feature. My e92 coupe has it and I use it almost everyday during the winter months in MD. Where are you getting your information from RVACHA?

[Bastet]

Originally Posted by Champagne

The reason for me asking is if this function would work as a hair dryer for when it's cold outside, just interested.

LOL Champagne ! Why don't you just move out of Sweden, it would be so much easier

The REST is a very nice function though when you wait for someone in the car during the winter ! And I bet the programmable ventilation will be very handy next summer in Tuscany

[GeriFix]

Originally Posted by Bastet

LOL Champagne ! Why don't you just move out of Sweden, it would be so much easier

<snip>

+1

I use my heater so infrequently that my last car still had a new car smell, after 3 years, when the heater was used (must have still been some protectant chemicals adhered to the radiator elements).

[Champagne]

Originally Posted by Bastet

LOL Champagne ! Why don't you just move out of Sweden, it would be so much easier

The REST is a very nice function though when you wait for someone in the car during the winter ! And I bet the programmable ventilation will be very handy next summer in Tuscany

Hehe, gotta finish school first Besides, the Swedish summers is something that I wouldn't trade for anything

[GeriFix]

Originally Posted by Champagne

Hehe, gotta finish school first Besides, the Swedish summers is something that I wouldn't trade for anything

Good point ... Swedish babes in bikinis

[Bastet]

Originally Posted by Champagne

Hehe, gotta finish school first Besides, the Swedish summers is something that I wouldn't trade for anything

That's why we come spend our holidays there from time to time

[Champagne]

Originally Posted by Bastet

That's why we come spend our holidays there from time to time

If you don't endure the winters, you don't deserve our summers! STAY THE HELL AWAY FROM SWEDEN!

hahaha

No but honestly, as soon as I'm done with school I'm heading out of here just to come to Sweden for the summers. Sailing around in the Swedish archipelago is truly outstanding and there's nothing like it. (maybe the finnish archipelago when I come to think about it)