I'll be doing this on the weekend. Thanks for a detailed write up!

Edit: Looks like my problem is fixed! As others have said, removing the wiper assembly is easy enough, and gives a lot more space to work.

Does anyone have the part number for the large plastic trim piece under the wipers that runs the width of the car? Mine is old and has chunks missing where it connects to the window.

 

Excellent tutorial. I just finished replacing the heater valve. Ended up with minor cuts trying to work around wiper linkage. Two 13mm nuts and one 13mm bolt allowed me to move the wiper linkage completely out of the way and really gave me the needed room to finish the job. Didn't have to disconnect electrical...just moved out of the way.

 

Hi. Where is the tutorial?
Also, does anybody have a tutorial f
to replace the dual valve (I believe it is under the front mudguard)?
Thanks,
daniel

 

Execellent DIY. My 211 E55 encountered the "no heat" issue Friday while driving to Whistler.
Logged on here Friday night and found this tread. Prepared to do the repair this week however heat returned yesterday on my drive back,but not for about an hour.
Wife drove car Friday morning and whwn she camy get something to work she will start pushing all the buttons. (car had been at dealer the day before and they shut everything off when its being worked on). Did my wifes button punching do something or is it only a matter of days before I go to no heat mode again?

Paul
North Vancouver,BC

 

I would really like to see a tutorial about that dual valve uder the mudguard.
Anyone?

 

Are you talking about how to replace the stepper motor for the heater? If so its this thread, first page : https://mbworld.org/forums/e-class-w...rol-valve.html


Canuck1: Execellent DIY. My 211 E55 encountered the "no heat" issue Friday while driving to Whistler.
Logged on here Friday night and found this tread. Prepared to do the repair this week however heat returned yesterday on my drive back,but not for about an hour.
Wife drove car Friday morning and whwn she camy get something to work she will start pushing all the buttons. (car had been at dealer the day before and they shut everything off when its being worked on). Did my wifes button punching do something or is it only a matter of days before I go to no heat mode again?

Paul
North Vancouver,BC

I believe it's very likely to happen again. It's only a matter of time because the valve fails mechanically. The teeth between the motor and the flap get stripped maybe. I never opened it up after I replaced it, but I definitely noticed a ticking sound like the sound of plastic teeth rubbing against each other after it failed.

Your wife did solve the problem, tho, even if just temporarily! At least that's what you should tell her :-)

 

[QUOTE=kurtwz;6219282]Are you talking about how to replace the stepper motor for the heater? If so its this thread, first page : https://mbworld.org/forums/e-class-w...rol-valve.html

Hi kurtwz,
Not sure if this is what I need to change. My problem is that the rea seats AC does not get cool air, only gets hot or room temperature air, while the front seaats AC works without a problem. Somewhere I rread that this is a problem from some dual valve situated under the front fender or mudguard. What is your opinion?

 

Just used this great write-up today on my 05 E320 CDI.
As mentioned it's much easier to just pull the wiper assembly which adds 2-3 min. to the entire job, but saves a lot of major effort.
I did Not read close enough and could have easily completed the job is less hen an hour, but was trying to twist out the outter hose connection. Not good as it's pinned and must come straight out, took me 20 min to figure that out.
On my CDI removing the engine cover creates a lot more room to access the outter connection.

Thx for the site & info.

 

I went to do this on my W211 E55.
The valve seems to be under the brakes, I cant work out how to get to it

Any suggestions ?

 

nice write up!

 

04 e320 with sudden no heat in Wisconsin in December this guided me through it thanks a lot

 

That was a great description, and it encouraged to me to do the job myself, particularly because, in England, the local MB specialist said it was a day's job. The reason for that is that these cars are designed for left-hand drive and then adapted for right-hand drive countries. This means that while the heater change-over valve remains in the same place, the right-hand drive cars have the brake master cylinder and servo moved to the right and positioned right on top of the valve, which makes its removal/replacement doubly difficult. The only way to get the new valve back into place is to ensure that all 4 hoses are removed from the car, and are connected to the new valve before forcing the valve and hoses back into place under the brake master cylinder. Working this out meant it took me a day and a half of putting the valve in and taking it out several times. So, if you have a right hand drive model, be prepared for a lengthy job; there is a YouTube video posted by another Brit which shows the problems that I encountered - but overcame in the end!

 

Yes mine is also RHD and near impossible to do.
ended up removing the brake master cylinder to get to it.
I thought that maybe it was just an E55 "feature ! "

 

Just changed mine couple of weeks ago. RHS.


1. remove brake unit (BOU), hardest part. Need to deactivate the SBC, remove accelerate pedal, brake pedal, flush brake fluid.
2. replace vale.

 

How long did it take ?

 

About 2 hours removing BOU,
20 minutes removing vale,
few minutes cleaning up.
15 minutes putting new vale,
20 minutes replacing BOU (once you know how to remove, it's much easier to reverse.)
You will need WIS instructions.


It took me 3 hours to flush brake fluid. (First round failed.) Must follow every step carefully.
You will need DAS.


It's worthy. You will have your cooling back, also smooth and responsive braking.

 

Thanks

 

This is an excellent DIY thread. Thanks to all who contributed.

There are two different heater control valves listed for the 2006 E320 CDI. One IS for cars WITH Auxiliary Heater (code 228) and one IS NOT for cars with Auxiliary Heater (code 228). Can anyone help me determine which part number I need? I do not know what the Aux Heater code 228 means or how to determine if it applies to my vehicle. VIN WDBUF26J66A955110.

 

I can't help on the VIN. I think the dealer can give you a readout. North American CDIs came with the aux heater. Curious, what are the part numbers for the two heater valves?

 

Thank you for the prompt reply and information. Unfortunately, I'm not located near any dealers. The car is a North American model so based on your comment, it has the Aux Heater?

211-832-05-84-M22 NOT for cars with Aux Heater (code 228)
211-832-06-84-M22 for cars with Aux Heater (code 228)

What is code 228?

 

Thanks for the part numbers.

You could call a service advisor, they might help. It's a good thing to have your car's code list.

Code 228 is the electric aux heater. It warms the interior before there is sufficient heat in the heater core.

Now I'm going to double check the part I replaced. It did not solve the problem that I was having.

 

Is this the same thing as the duo valve in an older Mercedes? Heater Duo Valve

 

Merc S500, 2000 model. I had a problem with the rear air conditioning for quite some time. The front AC would be nicely cool, but the rear always blew hot air, even with the temp set at low. Not related to that, I installed a new AC compressor. Now, the front AC is still ok and the rear now is nicely cool too!!! However, I set the rear temp to low and, after awhile it sets itself to 22 degrees celcious. So I need to keep changing it back to low. Strange behaviour, but certainly happy that rear passengers can now enjoy cool air in the summer. Any ideas why??

 

Merc S500, 2000 model. I had a problem with the rear air conditioning for quite some time. The front AC would be nicely cool, but the rear always blew hot air, even with the temp set at low. Not related to that, I installed a new AC compressor. Now, the front AC is still ok and the rear now is nicely cool too!!! However, I set the rear temp to low and, after awhile it sets itself to 22 degrees celcious. So I need to keep changing it back to low. Strange behaviour, but certainly happy that rear passengers can now enjoy cool air in the summer. Any ideas why??

 

Zambezi2,
In my S320 I had a simular issue bit it was from side to side. (maybe the back / never sit back there) drivers side blew cool the passanger side blew hot no matter what it set the temp to. It was the Duo Valve - they get dirty or clogged. I bought a used one off line after googling it. It also can be rebuilt if your so inclined.