shaungrey

Hi everyone, I think it’s known that a/c on our vehicles is not the strongest, but recently it was 25 degrees Celsius out and the a/c never really felt ice cold. Are there any specs with regards to air temp at the vents that I should be expecting? I feel like taking it in to the dealer will be a waste of my time, but wouldn’t mind verifying the temp myself with a temp gauge.
Thanks!

superswiss

Where does this theory come from that an AC needs to feel ice cold? That's uncomfortable to many people, and frankly unhealthy. An AC needs to be able to cool the interior to the set temperature. If it does that, then it works as designed. If it doesn't manage to get the interior to a reasonable set temperature, then it's malfunctioning. I'm not sure why some people think the AC in these cars are weak? Do you want your interior to feel like a fridge? If so, that's not gonna happen.

Don't know what year your car is, but 25C isn't really hot. I was actually out for a canyon run today in my 2019 C63CS (black on black btw). It was 100F (38C) outside, both my front tires were at 180+F (82+C), that shows them red in the instrument cluster. Had the AC set to 68F (20C) and I was comfortable despite working up a "sweat" from ripping through the canyon. I do have the ventilated AMG performance seats, so that keeps my back from sweating, but the AC had no issues keeping the interior comfortable under the burning California sun, and I didn't even have all the vents open, because I don't like being blown at with cold air. I have the outer two of the three center vents closed most of the time, and the passenger side vent is closed as well, because my wife doesn't like it open. I also keep the panoramic roof shade open pretty much all the time, including today. The glass seems very well heat insulated and I like the open air feel.

I don't think there are any specs, but you can measure your interior temp. How cold the air is coming out of the vents is largely irrelevant, as long as the AC manages to maintain the cabin temp at the set temperature.

Matthew Cohen

I also have a c450 and I have to come the same conclusion as you. The a/c in this car is just not that strong...Dont get me wrong, it works and it is sufficient and not defective, but on hotter days (~95°F+ (35°C+)) the air never gets truly cold. It is cool, and it does what it has to do, but when I have the sun baking me through the windshield and the air is just "cool"...that is not a fun time. I'm going to go to the dealer and see if they can give me a shot of refrigerant, hopefully that will do some good. If your a/c isn't that cold at 25°C, I'd say that is a problem.

stockbmw

Stick a meat probe or shoot a temperature laser at your vent. It should read 4C or 40F or lower. If not, your AC isn't working right.

shaungrey

Thank you for the replies. Yes I don’t feel 25 degrees is that hot but it seems to take 10-15 minutes of driving before the a/c feels cool, and probably 20 mins for the interior to get to the selected temperature. I can’t imagine what it’s like in hotter climates with 30 degree temps. Thank you for the 4 degree target, will see if it gets close to that.

W205_AMG

I live in AZ, its 115 outside and my AC has no problems keeping me comfortable. Maybe this just has to do with the 2017 model year? Mine is 2019.

superswiss

If the car is parked outside in the sun, then the interior is obviously very hot and the seats etc. store a lot of that heat that then has to radiate out again. The interior air might cool down quickly, but you are essentially sitting on an oven for a while, especially with a dark interior. All that stored heat energy has to dissipate first. What I do often on hot days is press and hold the unlock button on the fob to lower all the windows and open the roof to let the bulk of the hot air naturally escape before getting in. In my case this also immediately turns on the seat ventilation to start cooling the seat. If I really wanted to, I could also remote start the car from my phone 10 minutes earlier and let the AC cool down the interior, but I haven't felt the need to do that yet. I can definitely say that the seat ventilation makes a big difference in cooling the seats, even if it isn't directly felt at times. It circulates the cool cabin air through the seat and fans my back, which quickly gets that heat out and keeps me comfortable.

Sailorlite

If the air coming into the car through the vents is not refrigerated then the interior will not ever arrive at a cooler temp. It's very possible that your a/c components are not working, which is hopefully still a warranty issue.

As mentioned the incoming air should measure at around 40F.

It's also possible that you're experiencing an electronic "climate control" issue, but without 40F air there's little hope of a comfortable interior temp in hot weather.

jonathan358

Is your refrigerant filled? My AC gets cold within 2 minutes, maybe 4 on a hot summer day (35*C).

The problem for me is that the fans aren't strong enough, I need to turn it on setting 5,6,max for it to start blowing. Everything below it feels similar, if you were to graph the fan speed, it would be very non-linear.

zmaj126

Hi! I have a problem with my w212, a/c barely works, and diagnostic says there is a problem with communication with sliding sun roof, which my car doesnt even have? Any ideas?

jhpmbusa

haha this is accurate. you need at 5 and above to get it going. 5 is when the turbo boosters kick in.

White One

My last 3 cars were a CTS-V, Audi s4 and an M5...My c450 has the weakest A/C by a long shot..Pressures on both sides of the compressor are good, its just not as effective as the others were.

DrivingForce

Interesting. I test drove a C450 that was sitting out in the hot sun on a 90F day. I immediately noticed the AC wasn't nearly as cold as my W204 C300. Kinda disappointing but not surprising