W211 E220 Blowing cold air - Duo valve not only affect one side?

[pcman_jh]

My 2004 E220 CDI has just started blowing cold air - all other functions are fine i.e. it increases the fan speed thinking the car interior is not heating up fast enough, but not clever enough to know it's only cold air blowing through. Air con off/on doesn't make a difference.

I see there are threads all pointing to the Duo valve, but if it's 'Duo' surely only the only side of the compartment (his or hers) would be affected unless I'm unlucky and both have stuck at once? Also I see they tend to stick in the hot position, mine's is cold.

I've also read it's not an easy job to get to the valve, does someone have a worksheet or notes.

And lastly, is the Duo valve on this model (W211 not W210) something that can be opened up and simply cleaned?

Thanks in anticipation.

 

[BlackC55]

The duo valve on the 211's is a very common complaint. The component is located in a very awkward place and should only be replaced by a competant mechanic.

It is under the master cylinder.

I can be opened up and cleaned as the coolant gets into the motor and ruins it. New one only.

 

[television]

The pump could be at fault 300 in the link

http://www.detali.ru/cat/oem_mb2.as...GM=716.649&CT=F&cat=64U&SID=83&SGR=181&SGN=05

 

[Alex M Grieve]

I can be opened up and cleaned as the coolant gets into the motor and ruins it. New one only.

I suspect that, when you said can, you meant can't?

Do I get a toffee for vigilance?

 

[television]

I suspect that, when you said can, you meant can't?

Do I get a toffee for vigilance?

It has been done by members but hard to get to and up against the bulk head