HVAC Oder Due to Mildew in Heater Box on Mercedes-Benz C230

Problem Description and Possible Solution

The heating, ventilation and AC (HVAC) heater box is susceptible to mildew buildup. This can result in a musty odor from the HVAC system, most noticeable when the system is first turned on.

Problem Data
RepairPal Verified
Average mileage: 86,406 (45,000–140,000)
7 model years affected: 1999, 2002, 2003, 2004, more2005, 2006, 2007
17 people reported this problem
Viewing 1 - 6 of 6 comments
The car's AC has an awful vinegar smell that is pretty constant. After running for a WHILE, it gets a little better but not really. The problem has not been fixed, just tolerated.
Smelly mildew hvac
car makes everyone cough
I've had this problem for a long time, too...not just in my current MB, but previous ones, too. It's worse in summer than winter. I had it "cleaned/flushed" by the dealer on one of my previous cars and it did resolve the problem, but it was pretty spendy. Are there any DIY solutions?
I bought this car at 69,898 miles and now at 94,343 and still have this problem. my brother is allergic to mold and has a instant headache due to this problem. I smell it every so often, very often when its hot out and I have the AC on.