Volkswagen: jetta evaporator housing not draining, vw jetta, heat shields

Question
96 vw jetta trek; a/c evaporator housing drain blocked.i assume this is the problem.i have water draining into my passenger side floor with the a'c on.(not draining inderneath car)i cant find the drain hose under car..can u tell me where to locate it and do i use an air hose to blow it open?  

Answer
it is likely that the housing drain hole has diss-lodged from the drain pipe in the bulkhead. this is in the car, passenger side near the transmission tunnel / centre console. there is a plastic pipe which sits into another pipe with a foam collar round it. should this not be the problem, then you will need to blow through the pipe in the bulkhead as it goes to a rubber grommit behind the sound proofing and heat shields in the engine bay. ps, if the water leaks in all the time then the pollen filter housing may not be sealing properly on the passenger side, engine bay area below the windscreen. if this is the case then it will probably need replacing and resealing.