[AlecsNYC]

Apologies for a dumb question but I was wondering where does water/condensate accumulated by air conditioning system goes to? Is there a hose sticking somewhere through the floor letting water/condensate drip on the ground? Is it possible that water from A/C would accumulate on driver's side front floor? Just chasing unlikely source of leak. Thanks!

 

[plinker17722]

Try and catch some in a container the aircon drain off water is clear .

 

[kevdupuis]

There should be a hvac drain on the top of the trans tunnel that's known to disintegrate, also look at the windshield seal at the base of the glass I had water running between the seal and the glass and into the interior.

 

[AlecsNYC]

Oh, yes thanks kevdupuis! Thanks for pointing me in the right direction. I now understand the issue. Windshield seal is not an issue here. I know I have leaking windshield seals, both frond and rear. This is why I make it a point to use waterproof cover in the rain and not drive in the rain.

So after driving on a dry sunny day for 2.5 hours with A/C on (for the first time) I was puzzled to have found water in passenger compartment...

 

[MBZ300CD]

Here's what I did

Here is a post on my experience with the AC condensation drain.

http://www.benzworld.org/forums/w123-e-ce-d-cd-td/2385585-mbz300cds-300cd-7.html#post16152634

It also shows the repair I made and the correct Mercedes replacement part. The hose is easier to access from the passenger side after removing the lower panel. The insulation used was for 1/2" pipe.

 

[oldmako]

The short answer - It goes under the rug on the drivers side of the car and runs aft as you drive.

You must replace the evap drain tube. I cut the top off of a plastic water bottle and created a 2 inch funnel which I then jammed into the egress hole on top of the transmission hump. All in all, it was no fun. Mercedes cleverly designed and installed a little "gizmo" which protrudes from the bottom of the dash. That sinister little mofo jabbed the hell out of me every time I tried to get to the hole. I hope that you have very small hands and a young back. Good luck.

 

[VON]

When I replaced my whole unit behind the dash, I installed a plastic tube onto it, then slid the pipe insulation over it to fill the hole in the tunnel up. Never will I have an issue with a leak again!