BMW Repair: BMW heating system, heater core repair, bowden cable

Question
I recently had to replace my heater core due to corrosion in the pipes. Now when I turn on the defroster scalding hot air comes out no matter what setting. Is this related to the recent heater core repair?

Answer
Yes, I imagine that this is related. The Auxilliary water valve could be faulty or not plugged in or more probable is that the installer forgot to hook up a bowden cable or stepper motor that controls some blend air doors in the heater box. I would take it back or head else where for diagnosis and repair.
-Evan