tifosiv122

Vent?!?

Erik

FrankW

i mean what controls the air out of that vent? the auto mode does it by itself?

tifosiv122

Yeah, I was being sarcastic, sorry.

Erik

CitronC230K_03

ill read my manual when my car arrives

AndrewK

I'm confused about when they changed between these 3 variations. It must have been very late in 02 or early 03 because ours was a late-02 (May maybe??) build has all of the wheels.

MarkL

Guys -- here's some info about the 2 wheels you're talking about from someone who's had a C240 for over a year. The manual states some things about the "blue" wheel that aren't exactly right.

1) Wheel on vent on top of dash: (First of all, this is also a speaker grille for BOSE equipped sedans - I guess coupes too) The wheel directs air coming from the main center dash "face" vents upward to the dash. The manual states that in hot weather, this helps distribute the cooled air. Personally, I leave it set to direct only a small amount of air to the dash-mounted vent, since as someone else mentioned, it reduces air from the main vents. In heating mode, this wheel doesn't matter very much since most air is already directed to the floor vents. Someone asked what is the vent used for if the wheel is absent on the '03s. The center fill speaker is still under there for BOSE, so they need the grille anyway.

2) The mysterious "blue" wheel: This wheel has no effect when cold air is already being delivered to the "face" vents during A/C operation. In winter (i.e., heater operation), you can rotate the wheel upwards (exposing blue arrow) to force cold air through the center dash "face" vents. From what I've experienced, it does not affect any other vents. The idea is that you can add cool upper air, sort of like "bi-level" operation, when most of the hot air is being directed to the floor, without tampering with the "air direction" control on the climate control. I generally leave this wheel in the downward position -- some people have reported a slight whistling noise through the center "face" vent at high fan speeds. If you move the blue arrow wheel just slightly upward, this will stop the whistling.

avlis

I use touch the blue wheel quite often in the winter. Usually on cold, sunny days I like to have cool air blowing from the upper vents while the floor vents pump out the heat. If I leave the blue wheel closed (a little open to prevent the whistle), I get a trickle of heat coming from the dash which makes the upper part of the car (chest-up) too hot. That's with the Auto temp set to 66-68 degrees. That cool upper air makes things much more comfortable on cold days. In the summer it has no real use as MarkL posted above.

The question is: How do you get cool air from the upper vents during heating without the blue wheel?

jhillman

I have a 2003 C 320 sedan on order for 12/03 delivery and personally will be quite disappointed if either of the two vent controls in question are missing from the car.

First off, I like the top diffuser vent to help distribute cool air throughout the car. I have used this feature and really like it. If the rationale behind taking this feature away is reducing condensation on the windshield, and you could achieve the same result by simply turning the control off, I think it's rediculous they're doing away with this feature. Just have the service people tell people that bring their cars in for condensation issues to turn the vent off. Problem solved, yet you still have the functionality of the top diffuser. Right?

Second, why would you do away with the cool air control knob for the dash vents? All BMWs have this. All Mercedes have had this (I think). It makes total sense for the winter months. It is a comfort as well as a safety feature for long drives--the cool air on your face helps keep you alert, etc.

MarkL

Maybe they took these controls away due to naive customer complaints. I can't believe it's a cost issue since they've already got the parts in production. If they're getting hundreds or thousands of complaints, this could cut down on negative surveys, etc?? Just a thought.

I mean, one guy said: "The blue does not match anything and the wheel on the top vent just looks weird." With this type of viewpoint, it's a wonder a car can satisfy anyone . Like, the black accelerator, brake and clutch pedals don't match ANYTHING in my java interior :o .

tifosiv122

I was the one who said that, and I was the one who noticed the difference in the first place. With that said, let me respond.

I highly doubt anyone would seriously complain that the wheel was blue and out of place. I said I thought it was and I was glad that I didn't have it, yet I never said I would be upset if it did. No car can be perfect in everyone's eyes.

For the people with the wheels, if they are happy, so be it. I don't have what I believe are two useless wheels and I am happy about that.

I brought this up not to gloat that I don't have them, but rather question which cars do and don't have them. It is clear that there was a problem or lack of need for these 2 wheels and MB decided to remove them.

Erik

MarkL

Erik, I didn't mean to say that your comment, and my comment in my 1st paragraph went "together". I was just using your quote as an example of one person's view. I'm sure that the complaints that MB dealers usually get are condensation, fogging, "what the hell is this for", etc. In fact, some other people on this board have stated that they were disappointed that the wheels were gone and might not buy the car now! As with any topic, there are those on all sides of the issue.

No offense meant -- I was just making an extreme point.

revstriker

I agree with avlis in that the center "wheel" is useful in the colder weather to let in cooler air. I find myself using this a lot. Is there a way to do this on the newer models that do not have this wheel? I would think that in the colder climates, it would be a pain constantly adjusting the temp.

CitronC230K_03

isnt that the purpose of automatic climate control. i mean you set a temp and thats that. again i dont have much experience with this just asking a question, like i did with the rubber floors mats, and the such. dont have much experience, really none, with cold, snowy, weather. just trying to understand.

FrankW

IMO the climate control in the C-class sucks pretty bad. just two days ago it was about 54 degrees at night i had my temp set to 72. The two vents near the mirror were blowing warm air, and the center vent was blowing cool air. Yesterday it was about 56 degrees, same setting, but instead like two days ago, this time all the top vent blowed cool air and the bottom blowed warm/hot air at my feet. My feet was hot, but my upper body was cold.

I think the W208's climate control is much more accurate as heating/cooling the cabin to the set temperature goes.

Lynn

The automatic climate control regulates the overall temperature of the interior. The blue thumbwheel allows us to add some cooler outside air to the heated air coming out of the center vents. I like this feature. I usually want to keep my feet warm, but I don't want hot air bowing in my face.

revstriker

But the climate control keeps the entire cabin, top and bottom at the set temperature. On a cold day, If you set the temp at 72, it might be great for your feet and legs, but it may be too hot up top (especially if you're wearing a jacket). If you lower the temp, it may start to get too cold by your feet. By keeping the temp set up higher, and controlling some of the cold air up top, you can make it more comfortable. It sounds like you may have your center vent adjusted so that it is bring in the outside air (unheated). If you turn this all the way up (so no blue is showing), you should get consistent temperature all the way across. I have not had any problems with mine at all.

DCXdynodog

I drove an 03 loaner for week while they fixed my trans and it had the wheel in the (top) center vent.
This car did not have "premium sound."

My car does not have the wheel and it has "premium sound" (C5)

So, before I saw this thread I reasoned the fill speaker replaced the vent, but I did think it was odd to do that. (maybe they had no more room to put the speaker?)

Now I'm really confused :o :p

revstriker

Nope, my car has both the wheel, and Bose.

trench

My guess is that to save costs all 2003 cars get the same dash, Bose speaker or not.

Personally, I like the center fill vent and the (blue) cool air feature.

Is this a Coupe specific change or do the 2003 sedans also now lack these features?

Cheers, BT

o2bsurreal

This brings up a something about the climate control that I really miss which is a sun sensor. My 2000 Accord EX Coupe had a sun sensor on it's climate control which would redirect cooler air through the dash registers to keep you cool even if the lower registers still blew warmer air to keep the cabin at the correct temp. I read somewhere that the climate control systems of upper models have this, but not the coupe. Perhaps they decided to include it on the coupe and don't need the knobs so much anymore? I dunno - just a random thought.

trench

I thought that the little black dome on the vent in the hood was a sun sensor.

Nevertheless, I was under the impression that the C-class did have sun sensors.

- BT

o2bsurreal

I think it is a sensor which activates the lights, etc., but doesn't affect the climate control... from what I understand or have been able to tell anyway.

MarkL

I'm pretty sure the C230/C240 system has a type of sun sensor, but the C320 system is somehow more sophisticated (multiple sensors)? I don't think any climate control system will operate correctly w/o a sun sensor due to the sun-loading temperature factor even in cold weather. I think there was a post about this earlier but I don't have time to scan right now...

MB-BOB

I don't know for sure, but why can't a sun sensor be the input device for multiple uses? I remember reading in the brochures that the sun sensor not only reads light intensity but also reads sun angles.

I also thought that the dome in the hood vent is the sun sensor, but don't recall any previous thread specifying so. Although I can't think of any other likely suspect visible on the car.

Pass to next...

Outland

This thread is a real hoot!

I have the third wheel, and I wouldn't give it up willingly. Its nice for letting in fresh cool air when the the heater is on. I find the one on the Bose centerspeaker grille far less useful.

Since we are talking about the wheels, any C320 owners want to tell us how those things are lit up? I'd like to light mine up.

BTW and FWIW, the blue on the wheel matches the markings on the climate control temp settings....it would look really 'cool' lit up...