[onixxf]

I don't know what more to say, it's cold on driver side and hot on passenger. What gives??? 01 R170 320

 

[mike350]

I don't know what more to say, it's cold on driver side and hot on passenger. What gives??? 01 R170 320

Search this site for ‘duo-valve’ and you’ll have the answer, it’s a well known fault with either a sticking or faulty valve on the unit that controls the split heating system. Normally an easy fix.

 

[Avel Du]

https://www.slkworld.com/gtsearch.php?q=duo valve

some 'light' reading for you.

 

[Stuttgarter]

Also make sure your system is fully charged - Mercedes are known to have different temperature on driver/passenger side when low on Freon.

 

[M4rCu5]

Duo Valves
@Avel Du

Why is this thread in off topic and not R170 General?

 

[jbanks15]

I moved it to r170

 

[Avel Du]

Duo Valves

@Avel Du

Why is this thread in off topic and not R170 General?

I like to leave the odd OP post in the thread it was created in.

If I move them all Jeff gets bored. >

 

[M4rCu5]

@onixxf

Watch the video in JaysonM's sticky in the R170 DIY Section - HERE - as Jayson says, it's not an R170 in the video but it's pretty much the same, just wrap a towel or something around the base before you start to dismantle it as little things have a habit of dropping down the side of the engine, never to be seen again. :surprise:

 

[Mslisaj]

I had the very same problem. Duo-valve is simple to work on. It took me all of 30 minutes to clean the crud off the solenoid pistons and put it all back together and problem solved. I think I lost a cup of coolant in the entire process. Good luck and you'll be so happy it was that easy to fix.

Lisa

 

[Dave2302]

Hi,

Quick "Dave tip of the day" :wink: ...............

I always use a pair of Brake Hose Clamps, one either side of the component when working on bits like this, avoids all the hassle of having Coolant loss and potential of Airlock upon re filling :grin:

HTH, Cheers Dave

 

[JamesOMG]

I’ve had this problem before - same car. It was a open heating valve caused by a jammed solenoid, there are two, one for each side of the car. The solenoids are pretty easily accessed to change, however Mercedes replacement price is exorbitant. My car had Bosch solenoids that could be prised open. I found that there was a piece of grit jamming the solenoid, removed it, put the solenoid back together, and presto! Did the repair many years ago and all working well.