Octavia II -05 G65 sensor change

Got fault code from friends car, and asking how to find out can it be changed without draining the system??

That's the refrigerant pressure sensor, right? Unless there are valves that allow it to be isolated I don't see how it would be possible to change it without draining and refilling the system.

-Uwe-

PS: Moved to General VW/Audi Repair.

Yes that's the one. I read somewhere that there are two types of ac systems in these cars, and to another it's possible to change the sensor without draining.
Just can't remember where i read it......