W211 Heating Stuck

[Alps]

Weird problem i have had over the last few times I have driven the car.

Battery went flat, recharged and then the Air out of the vents would not get hot, it was freezing cold aircon air, reset all the flaps using STAR and everything was fine again. A Week later, same again freezing air, but after switching on\off the Air got REALLY HOT! and i couldnt cool it down, just ended up switching the fans off!

could this be the little valve thing under the wiper mech, i assume its a bit like the DUO Valve in the w202?

any ideas ?

thanks

 

[SavMan]

Alps

I had mine stuck on cold but only once, I gave it a slight tap with a large screwdriver. I have also heard people talk about parking on a hill but cant remember if it was facing up or downhill. I think you need the engine running and the settings the opposite of whats coming out.

 

[jaymanek]

Yes duo valve... Very common on W211. Part is cheap but its a fun job.

 

[mersum1es]

DIY: Installing a new Changeover/Heater Control Valve - MBWorld.org Forums

 

[rpe2]

DIY: Installing a new Changeover/Heater Control Valve - MBWorld.org Forums

Remember it's a comparative doddle on a LHD car, on a RHD car the master cylinder is in the way making it (as noted above) a fun job.

 

[Alps]

Sounds like this ones going to be fun!

Thanks guys will order it in

 

[beaker218]

MB dealership charged me £120 for supply and fit on my W211 2 years ago

 

[Dieselman]

MB dealership charged me £120 for supply and fit on my W211 2 years ago

WOW. That sounds incredibly cheap.

 

[jaymanek]

That is a bit tooo cheap... the part is only £30 but fitting it is a few hours.

 

[sinewave]

'Somebody' probably quoted it wrong but by the time they realised, it was too late, so they had to stand by their price!

 

[mct_cars]

Duo valve is down as 4 hours on the WIS. I've seen it done in around 2.5 by someone who'd done a few before. My guess is they quoted you for LHD.

 

[beaker218]

I must admit I thought it was a bit cheap too when I noticed that the master cylinder was in the way of the valve so I didn't complain about the price! although I did think at the time that maybe they had an easier way to get to the valve and that's why I was charged only £120.