A different A/C problem
 

Not looking to repair it myself,,, it's under warranty,, but any ideas might be helpful for the dealership. My 07 E350,,, when you start it up and hit Auto on the climate control, it takes 4 to 5 minutes to start blowing any cold air,,,, I mean it throws HOT air, full blast, at you, and depending how hot it is, you might have to wait outside, until it decides to cool. It seems to be related to engine temperature, as when it get a bit over 60c, the cold air starts flowing. The compressor is engaged all the while, but something seems to be keeping a valve closed until the engine warms up,,,, strange. It has been in once for this problem and going in again next Monday. Just wonder if any dealer techs have ever seen this problem.

It sounds like the dual valve may be faulty. Had the same problem on 98, but once I lightly lubricate the dual valve the problem was fixed. In this case you should let the dealer take care of it.