DUO VALVE SIEMENS CLIMATE CONTROL. 97 E-300. TD.

[HERBIEMERCMAN]

Hello everybody, Not sure how many members have been involved with the w210 heater / climate control. I have repaired my 22 year old duo valve several times but now it is time to replace it, it is 'letting by' when the valve is supposed to be closed,and on hot days your getting heat you do not want.
Anyway, i have obtained a valve from 'Three Pointed Parts' it has been tested and cost one third of the OEM price for a new one.
My question is how to remove the valve, it is mounted on a sort of rubber bushes with conical tops, and the two engine water pipes on the underside of the valve there are two straight water connection nozzles which must push into the plastic elbows which terminate the engine water supply pipes, there must be some kind of 'O' ring inside the elbows to make a seal?
So does anyone know how to disconnect the rubber bushes which support the valve assembly and how to disconect the pipes on the underside. see pics. Herbie. nnect the underside water connections ? Any advice will be appreciated. Herbie.

 

[HERBIEMERCMAN]

Hi Everyone, Some members may want to know how to replace the duo valve, you disconnect the electrical plug, you then force the rubber connical pegs through the fixing holes in the fixing plate which the valve is mounted on, you then then expand and pull off the two heater supply pipes which are on the side of the valve, then the tricky bit, you take a small screw driver and ease off the stainless steel clips which connect the other two heater pipes which the valve sits in, you can then gently rock the valve from side to side and lift upwards, that exposes the two plastic elbows which contain an 'O' ring for the pipes on the base of the valve to seal onto, and that is it. With the position of the valve being so high up on the engine, then little or no coolant is lost.
Hope this helps someone. Herbie.

 

[umblecumbuz]

Goodness Herbie - is your car falling apart so early in its life?

 

[HERBIEMERCMAN]

Goodness Herbie - is your car falling apart so early in its life?

Hi umble, I have 260K on the clock now, had her from new in 1997, the list of replacement parts is very long but not too bad when it is 23 years young. Following the respray and 'waxoyl' every 2 years the car is superb, started to get admirers now as there are not many of these about and it looks like a real Merc, still has one of the best load carriers out there. The only thing falling apart is me, not the car. lol. Herbie.

 

[Doug1234]

This link will explain how to remove it
http://www.peachparts.com/shopforum...-w210-got-my-heat-back-saved-myself-$250.html

Once you get new one back in then after fitting the coolant hoses push the top one back a bit and insert a very thin screwdriver between it and the pipe it sits on.
Now you can gently tease the screwdriver up to bleed air out of the cooling system with engine running and heating switched full hot,this is the highest point in the cooling system so once coolant starts to appear you can pull screwdriver out.
Its a complete pain to refit the hose on a hot engine as it will burn your hands ,
Using the screwdriver this way means the hose is already fitted.

 

[HERBIEMERCMAN]

The replacement valve from 'Three Pointed parts' works perfectly, the modulation at various temperature settings is much better than the original valve.The most important thing is it actually shuts off completely and on hot days that is important. Herbie.