Sportstick

I usually hang out on the W204, as that's mine, but my wife's ATC performs so differently than the system in the C Class, I was looking for opinions/experience. In the C, when set on AUTO, the system will find the proper temperature and the fan will settle down while it very nicely holds the ambient temp in the cabin. In the W211, it sounds like we're on the edge of a hurricane, and even after the temp is comfortable, the fan is always running higher than expected, generating more noise than desired. We frequently have to simply take the fan down manually. I know this is all governed by software...any ideas if this is abnormal? Thanks!

P.S. Yes, I did search first!

Sportstick

This sure is a quiet forum...I guess that goes with being an E Class? 100 people have read this post and no one has any experience or comments to share?

Scambo

My AC is very loud from the outside, sounds like a turbo train is coming. No problems with noise inside, although I wish the blower would produe more thrust for front and back passengers.

Trey

My 08 E350 was doing the same. I checked all the vents and found the passenger side and the rears closed. Opening those helped somewhat, but it still seems to run faster/louder than it should. Next time I'm in for service, I'm going to ask if there is a software update available.

SZMB

On my 2004 E500, when set the temp to auto mode, the fan runs at full blast for a long time even after the temperature reaches a "comfortable" level, as you've described. And yes, I usually manually lower the fan speed after reaching a comfortable temperature. I think the fan motor is much powerful than the C class partly due to more space volume to cool. I had a 1988 C280 previously, and the fan was no where as powerful & loud as this E500. The noise generated from the engine is more like a hurricane -- it's definitely a force to be reckoned with.

gaazmon

ya the damn thing sounds like a rocket about to take off

Sportstick

Thanks everyone! Based on your comments, it certainly seems that this is at least not an individual defect with my car. I will also ask if there is a software update which calms the fan down once the target interior temp is achieved. I understand the issue of relative interior volume requiring greater output, but this does seem quite disproportionate and certainly much louder and higher fan speeds than ATC systems in comparably or larger sized competitive makes.

Barry45RPM

Raise the temperature setting you have selected as soon as you are comfortable in the cabin & leave it set at that new number. Right now you are becoming comfortable while the car is still chasing your set temperature. ...because as soon as the temperature you dialed in (assuming you are comfortable) is the same as the current temperature in the vehicle, the blower speed will drop to a lower speed.

The number on the display when you are comfortable will surprise you... its NOT the same number you have your House thermostat set to.

Thats why you feel as if the blower stays on high longer than necessary. ...remember, whenever your dash control unit is in MAX mode, (Manual MAX or regular DEF modes) the radiator fan goes into that screaming loud mode under the hood to dissipate heat.

braizedtofu

Well said barry. OP, your "comfortable" temperature is subjective. So even if you feel "comfortable" most likely youre not at the set temperature yet. Honestly I doubt theirs a software upgrade for something that is working the way it should. Merc obviously knew that most of their owners are impatient and want instant gratification, and the only way to achieve that in the shortest amount of time, is to use a higher fan speed. The downside is increased noise. Seriously i think youre just being overly sensitive about something that is totally in your control. As with all things in life, you cant have it all, compromises will have to be made.

I agree my e500 makes a lot of fan noise on auto, but like what was already suggested, turn the temp up or manually control the fan.

Happy 4th all!!

Barry45RPM

That's probably why on the 07s > the second you press Auto, the fan speed indicator dissapears from the display. (on th 06s < the fan speed indicator was always on display). They probably wanted to get peoples mind off fan speed.

On a really hot day, the A/C can't pull the cabin speed down to a real 69 anyway, so if you raise the temp to a setting the unit can satisfy, your interior fan will come off HI, and your underhood fan will drop in speed too, not making that Everglades Boat type of racket.

Trey

The reason I don't believe we are being "overly sensitive" is this is my 8th Mercedes and the only one that has done this. Yes, comfort is subjective and yes, each car has had it's own temperature setting to make me comfortable. But this is the only one that has run at noisy fan speeds continuously. No matter the temperature setting, the fan seems to run too fast even after cooling the car down. Raising the temperature does not seem to make that much difference - it still runs too high. My other cars will lower the fan to imperceptable levels at times, but not this one.

charliele729

When the fan is on full blast, it really does sound like a crazy hurrican with a really faint wine to it. Though it was something but I guess it just normal. As long as it keep me cool with cold air, I am good. How often do people drive with the fan at full blast for a longer period of time anyways???? Not very long.

Barry45RPM

My Wife's 128i BMW Conv's underhood fan screams like a Turbo Prop airplane. Some cars run hot & have to dissipate a lot of heat.

Clinton Horn

It appears to me that the engine bay fans are stuck in the maximum mode. I have an older 211 but it does calm down once the user dials up the T/Stat.
Personally, I applaud the way it works. A black car in the south can get pretty hot when parked. The blower and cooling fans come to life at full bore instantly when "auto" is pushed and 70 degrees on the stat. Yeah, the noise is pretty bad but mostly outside of the car.Others may be annoyed but I enjoy the delivery of icy air and plenty of it. Intuitively, I would say that it reaches a comfortable level in the cabin in about 2 minutes while our silver Maxima takes about 4-5. Those engine bay fans draw plenty of electrical power. Continuous high speed running at idle will put a serious current draw on the battery. I have no idea what is causing yours to stay at max but it is not what I know as normal.

charliele729

Maybe this is one reason why our battery are so large comparing with other cars. I took a look at our battery in the truck and have to say that it is by far not a normal size that I see in most sedan cars.

Trey

The thread has moved off subject. The original poster and I are talking about the blower motor running fast, not the radiator fan.

Yes, the radiator fan sounds like a hurricane, but that is normal for these, and a lot of other cars nowadays. The blower fan on our cars also runs high (in our opinion anyway,) causing the interior of the car to be noisy and cold. It does not seem to slow enough once the interior of the car cools down. Raising the temperature helps somewhat, but the fan seems to still run faster than any other car I've owned maintaining temperature.

Anyway, just thought I'd try to clear up what we are experiencing.

AAlfarah

Hi, I bought my first MB about two months ago, and since then it has been a problem after another. after changing all the front suspension and mounts, I turned the car on and the radiator fan kicked about 10-15 sec, I think it has nothing to do with me replacing mounts since I did not disconnect any wires while working on the suspension and mounts, but I unplugged the fan's connection (the one on the fan closer to the passenger side head light) and I saw some kind of green corrosion on one of the pins the smaller pin hole on the left side of the plug.

I just want to add that my AC have been out since i bought the car, could that be a related matter?
Please help!!!!