Heater still blowing warm on cold setting - Where's the mono/duovalve?

[motovelo]

My heater still does not work properly on my 412 Sprinter, I've been advised elsewhere on here that it's the monovalve and these can seize. Where is it and how can it be freed off? Thanks

 

[C220GJS]

Can't find your duovalve , if you have one ?, on the Russian site, but if you have a look at POD's guide you may be able to find it and clean it ;http://forums.mercedesclub.org.uk/showthread.php?t=25909.If you find it ,check the wiring plug is making good contact first.

 

[television]

They do not have CVs on the rusky site, if you cant find it,I will find it for you