Go Back  MBWorld.org Forums > Mercedes-Benz Sedans > E-Class (W212)
After starting, A/C blows hot air until driving...it's fine for the rest of the drive >

After starting, A/C blows hot air until driving...it's fine for the rest of the drive

Notices
E-Class (W212) 2010 - 2016: E 350, E 550

After starting, A/C blows hot air until driving...it's fine for the rest of the drive

 
Old 03-28-2017, 10:19 PM
  #1  
Junior Member
Thread Starter
 
Join Date: Nov 2007
Location: Georgia
Posts: 33
Likes: 0
Received 0 Likes on 0 Posts
2011 E350 Luxury
After starting, A/C blows hot air until driving...it's fine for the rest of the drive

After parking my car at work all day, the interior is very hot given that the ambient temp is in the upper 80's. However, once I start my car ('11 E350), the air conditioner blows warm air at full blast.....until I begin driving. I've sat for up to 10 min after starting and it continuously blows hot air....until I begin driving. Once I pull onto the road and reach 30-40 mph, cold air immediately begins blowing and it's VERY cold at that point. This isn't an idle problem I don't think because once the air begins to blow cold, it KEEPS blowing cold even at stop lights or at any subsequent idle situation. Even after driving to the grocery store and staying inside for over half an hour, the a/c still blows cold air once I restart the car with warm engine.

Therefore, the only issue is after the car has sat all day. I hear the cooling fans kicking in (the jet engine sound??) so I'm assuming they're functioning properly. Normally, I'd say this is just a characteristic of this car's a/c system but, this is my third E350 and I've just recently gotten out of a '10 ML350 and none of them behaved this way after sitting all day at work. Therefore, I won't accept the "it's normal for a hot car to act this way" explanation.

Full-disclosure, I've checked nothing on the car other than making sure the big fan up front is turning. Any thoughts or anyone have similar experiences?
khelms_98 is offline  
Old 03-29-2017, 01:37 AM
  #2  
MBWorld Fanatic!
 
thenew3's Avatar
 
Join Date: Dec 2003
Location: Carmel, CA
Posts: 1,041
Received 74 Likes on 65 Posts
2013 E350 Sport Wagon, 2016 X3 sDrive28i
Maybe the AC's freon needs a top up. I had similar symptom on a previous car and it was the refrigerant/freon in the AC system had leaked a little so it was a little low. Dealer topped it up and it started to blow cold air out within a few seconds of starting the car.
thenew3 is online now  
Old 03-29-2017, 10:52 PM
  #3  
Junior Member
Thread Starter
 
Join Date: Nov 2007
Location: Georgia
Posts: 33
Likes: 0
Received 0 Likes on 0 Posts
2011 E350 Luxury
Originally Posted by thenew3 View Post
Maybe the AC's freon needs a top up. I had similar symptom on a previous car and it was the refrigerant/freon in the AC system had leaked a little so it was a little low. Dealer topped it up and it started to blow cold air out within a few seconds of starting the car.
Once I start driving, today it was while I was still in the parking lot, I hear a very brief hissing sound then very cold air immediately begins blowing. Still sound like I'm a little low on freon? I'm clueless about AC systems. Thanks!
khelms_98 is offline  
Old 03-30-2017, 03:58 PM
  #4  
Senior Member
 
Join Date: Sep 2013
Location: Bandon, Or.
Posts: 320
Received 33 Likes on 32 Posts
2013 E550 Sedan
I would have your blend air door actuators checked, it could be a blend air flap sticking. My 2013 E550 will sometimes take a few seconds after moving before the defrost will start blowing air on the windshield.
davidjohnbamber is offline  
Old 03-30-2017, 04:15 PM
  #5  
MBWorld Fanatic!
 
thefisch's Avatar
 
Join Date: Mar 2014
Location: West Central Florida
Posts: 3,082
Received 313 Likes on 272 Posts
2011 E550 P2 4M Sedan
Could be an issue with the clutch on the AC compressor. Could be a relay issue. I had a relay issue on a Honda and it was a cheap DIY fix, but it was easier on that car to observe the compressor engagement.
thefisch is offline  
Old 03-30-2017, 08:50 PM
  #6  
Junior Member
Thread Starter
 
Join Date: Nov 2007
Location: Georgia
Posts: 33
Likes: 0
Received 0 Likes on 0 Posts
2011 E350 Luxury
So the fact that driving corrects the issue every time, it could still be the blend door actuator or the AC clutch? As I said, I'm pretty ignorant when it comes to AC systems. Thanks again for the help!
khelms_98 is offline  
Old 03-30-2017, 09:44 PM
  #7  
Member
 
Join Date: Apr 2011
Location: Bradenton, FL
Posts: 96
Received 5 Likes on 5 Posts
'12 E550 4M, '14 ML5504M
The hissing is key; if you hear it, the system is expanding the refrigerant appropriately. It should be regular but intermittent. I would go with simplest solution, which is the refrigerant has migrated out of the system and now just low. Dealerships will insist they are sealed and should not leak, and try to charge you for a system flush and stuff, but over time, the refrigerant will migrate out of the system as a matter of course. If they top you off and the problem persists, then I'd look for something more extensive.
iGeorge is offline  
Old 03-31-2017, 02:07 PM
  #8  
MBWorld Fanatic!
 
thefisch's Avatar
 
Join Date: Mar 2014
Location: West Central Florida
Posts: 3,082
Received 313 Likes on 272 Posts
2011 E550 P2 4M Sedan
These are hard to diagnose. I keep a cheap refill kit around to test pressure but you have to make sure the compressor is running. If you can see the compressor pulley you should be able to tell if the inner clutch is turning or not.
thefisch is offline  
Old 07-12-2019, 04:31 PM
  #9  
Newbie
 
Join Date: Jul 2019
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Mercedes C300
I have the same issue but didn't try driving yet. It's hot forever unless I turn the engine off and on again. Then the air is really cold. What's up with this anyway?
MyMBUSAcar is offline  
Old 07-12-2019, 04:31 PM
  #10  
Newbie
 
Join Date: Jul 2019
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Mercedes C300
Thanks, I'll try that.
MyMBUSAcar is offline  
 

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

Thread Tools
Search this Thread
Rate This Thread
Rate This Thread:
You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: After starting, A/C blows hot air until driving...it's fine for the rest of the drive


Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: