Heater control C250 TD

[John Rodgers]

Hello everyone,
Having a problem with heater control.(drivers side ). Tempeture control only works sometimes, mostly it stays hot even with air con on and turned to the coldest.The passanger side works fine.My car is a 1998 C250 TD with 80000 miles ,
Hoping to hear from someone.

 

[Dieselman]

Either the rotary temperature controll potentiometer is dirty internally or the heater control valve is leaking.

Try swapping the connection on the duo valve to see if the fault goes with the valve or control pot.

 

[John Rodgers]

Thank you for your reply,Would it be good enough to swap the wiring over instead of the pipe work.hoping to hear from you soon.
Thanks again .

 

[Dieselman]

Yes, swap the electrical connections. Obviously the heat will come out on the opposite side to the control but it will prove whether the control pot can control the other valve ok.

 

[DrNick]

I have a similiar problem on the passenger side control. Mine only seems to go hot when it is set to the white setting. If I turn it to hot and then back again, it will go to the correct setting for anything from 2 minutes to 2 weeks before going hot again. I've never noticed it on any setting other than the white setting, but that could be coincidence!

Where is the duopot located?

Thanks

 

[John Rodgers]

swaped wiring around and every thing worked in reverse,and when i changed them again everything is working as it should .
I can only keep my fingers crossed
Thanks again

 

[NormanB]

The pots in the control panel get dirty.

If you work the dials through their full range for a couple of minutes it can help.

There is a proprietary spray cleaner and lubricant for potentiometers but for the like of me I cannot remember waht it is called (Brain Fart ) Try Maplins or Tandy they will have it.

 

[jaymanek]

Tandy!!! Didnt they all close down about 10 years ago?

Jay

 

[NormanB]

Tandy!!! Didnt they all close down about 10 years ago?

Jay

Well give Tandy a miss then
It was late - I was tired

NormanB

 

[NormanB]

Tandy!!! Didnt they all close down about 10 years ago?

Jay

Spookily enought see where this URL takes you:

http://www.tandy.co.uk/

Ho Hum

Microsoft and Amazon are taking over the world.

 

[Dieselman]

The pots in the control panel get dirty.

There is a proprietary spray cleaner and lubricant for potentiometers but for the like of me I cannot remember waht it is called (Brain Fart ) Try Maplins or Tandy they will have it.

Switch cleaner.

 

[NormanB]

Switch cleaner.

I would but I am married to her!

 

[PJH]

Temp control wheels

My driver's side temp fluctuates.
I have discovered that the driver's side temp wheel is slightly loose but the passenger side is a tighter fit.
Anyway, if I push the temp wheel side-ways the temp rises. So probably potentiometer contacts as Dieselman said above..