Volkswagen Repair: Polo Airconditioning gas leaks, gas leaks, schrader valves

Question
Hi,

I have a 2005 Polo 1.9tdi, its been leaking A/C gas for over 2 years now. Its been in and out the shop and they replace this and that but cant seem to find the leak.

They (dealerships) have changed the pump ,condenser ,pipes and expansion valve, but after 3-5 weeks it still leaks the gas.

Is there a common problem that they overlook ? Maybe a part thats hidden and not so obvious to see ?
Any help or direction would be appreciated.

Thanks
Gerrit

Answer
Hi Gerrit;
I hope I'm not suggesting something too mundane...but, what about the "Schrader" valves.  I've had Passat's with this same problem, and the "Schrader" valves cured it for over a year...it still leaked, but very, very little.  Hope this is an improvement for you.