[A8] water accumulating in the vent system

[Calvin Liu]

I did a full service on my air conditioning in December; since then water has 
accumulated in the vent system twice; the first time to the point of spilling 
out the rear AC vent (and requiring ripping out everything to dry out). I 
thought something might be plugged; took apart the front drainage and found some 
obstruction in the drains above the engine.

However, this wasn't the problem as the mass of water has returned.

Could I have done something bad during the AC service, or perhaps a lower drain 
vent from the vent system was plugged somehow?

Calvin Liu
2003 S8