valentinasmj

I have noticed that the rear vents (especially) on my E450 wagon are uncomfortably loud when the fan setting is on high, but they need to be on high to get air back there. I will fiddle with the climate style, I did not even know that existed. We have only had the vehicle for about 9 months. We are new to MB but the controls for everything from the GPS to the audio to the AC are far more complicated and tedious than I expected.

BACnMercedes

Ours works great and even after a few minutes the fan will slow down. We use the auto feature and have the temp set to 68 degrees. We also have the acoustic comfort package so that may help some too. We have also closed the vents in the B pillar, not to help with cooling but they were just too loud right behind our ears in the front seats.
I haven't had a bunch of different vehicles to test against, but our E class does seem to do a little better than our GLE and a lot better than our BMW we just unloaded.
(On a side note, I have noticed our E class does even better at cooling if I switch the car to sport plus. In that mode the car idles up a little higher and therefore it seems to cool better and faster. I don't need this mode though to cool better though, just an observation.)

TPAbnz

Perhaps that's not in the '17s? The only settings I have under climate is ionization and the Airbalance fragrance.

whoover

My 2019 doesn't have it, either.

CaptainE

My 2019 doesn’t have it either.

Wasabi? Odd.

Haag

It's a feature of the Thermotronic 3-zone climate control option

DFWdude

I find this hard to believe (using CO2 as refrigerant). I believe auto manufacturers discontinued using freon under govt pressures due to systems that leak Freon over time. Leaking CO2 from the same systems is no different.

I'm not a tree hugger... just making an observation that substituting one greenhouse gas for another makes no sense. Especially among companies imposing drastic measures like ECO Stop/start systems on it's vehicles to control gas mileage/emissions, yadda yadda.

One might expect vigilant regulators in Europe to crack down on this mach-schnell, no?

whoover

Freon's main problem is ozone depletion, not greenhouse effect.

DFWdude

LOL, Chlorofluorocarbons (CFC, sometimes branded as Freon) is the ORIGINAL greenhouse gas...

"Most uses of CFCs are now banned or severely restricted by the Montreal Protocol of August 1987, as they have been shown to be responsible for ozone depletion.[5] Brands of freon containing hydrofluorocarbons (HFCs) instead have replaced many uses, but they, too (ie., like CFCs), are under strict control under the Kyoto Protocol, as they are deemed "super-greenhouse effect" gases."

https://en.wikipedia.org/wiki/Freon

A current TV documentary notes that the ozone hole at the south pole has stabilized and is starting to recover, 30+ years after Freon was banned. That's good, I guess. But regardless, I can't imagine govts retreating on its banning.

Meanwhile, there is little doubt that uncontrolled CO2 is a greenhouse gas. CFCs and CO2 are peas in the same pod.

whoover

Yes, CFCs are greenhouse gases, but the quantities of refrigerant leaks are minuscule compared with the volume of CO2 we pump out. It was the much more potent effect on CFCs on ozone that caused their ban. Replacing them with CO2 will not have a deleterious effect on the ozone layer and will not significantly increase atmospheric carbon, which is why it's being considered for refrigerant. If the entire charge in an auto climate control leaked, it would be equivalent to a typical gas-engined car driving a few feet.

chassis

Refrigerant regulation is not much different than tailpipe emission or fuel economy regulation. R12 was the “bad guy” and R134 was the “good guy” when introduced. Now R134 is the bad guy and something less environmentally impactful will take its place. And so on.

Haven't heard of any car company using CO2. I’ll check it out as I have a peripheral involvement in this professionally.

vic viper

Mercedes do use R744 (Co2),
they never wanted to use the flammable R-1234yf and made several production workarounds to avoid it, finally after an expensive and long legal battle they were forced to use it.
In some Mercedes vehicles with R-1234yf they have installed an extinguisher system in the engine bay to prove how dangerous the gas is.
This was done while waiting to the R744 to be fully developed.

chassis

Tested my 2017 W166 GLE350 tonight. Temperature measurement with via digital cooking thermometer.

Ambient temperature: 85 deg F
Ambient relative humidity: 61%
Engine temp: warm (needle in middle of gage)
Engine speed: 600rpm (idle)
Transmission gear: Park
Vehicle speed: stationary
Temperature monitoring location: register (duct) to the left of the COMAND screen, in other words between the instrument cluster and the COMAND screen
Climate control setting: MAX COOL
Air register outlet temperature after 5 minutes: 47.8 deg F and dropping very slowly

What is the target outlet temperature for Mercedes air conditioning systems?

chassis

Tested a 2018 G01 BMW X3 tonight. Same procedure as above, only difference was engine idle speed and climate control setting.

Engine speed: 850rpm (idle)
Climate control setting: MAX AC
Air register outlet temperature after 5 minutes: 49 deg F and stable

chassis

Tested a 2005 Toyota 4Runner 4.0L tonight. Same procedure as above, only difference was engine idle speed and climate control setting. This vehicle has 206,000 miles and a known refrigerant leak. Refrigerant was recharged 2 months ago.

Engine speed: 800rpm (idle)
Climate control setting: AUTO
Air register outlet temperature after 5 minutes: 48 degrees and slowly dropping