Hot And Cold Aircon?

[crash406]

my 300td eclass w210 blows hot air sometimes when the dial is set to blue, but also blows cold sometimes its 50/50 does this mean get my aircon gassed up or duovalve problem, or even pollen filter any help would begrateful ..

 

[BlackC55]

It is probably a duo valve problem. Somwhere there is a diy guide on cleaning them.

But faulty a/c sensors can cause similar problems. The evaporator temp sensor is a favourite.

 

[LastMinute]

There's a duo valve HOWTO [THREAD=26888]here[/THREAD].