Air con in the td5 is running well, ice cold and gets there quickly etc.

However I've got the wet carpet problem on drivers side after I use the air con for long periods, so I check the drains and they're clear and the gear box is dripping wet with water underneath them so they're obviously working. So how come I still have wet carpets? It's clean water, doesn't smell of anything and I don't get any musty/stale smells from the air con when I use it.

Could the drain pipe be damaged or blocked under the carpet and leaking? Anyone ever had to lift the carpets to fix drains from inside the car?

Cheers,

Yep sounds like drain tube has pulled off the heater box on that one side, you just need to pull the carpet back on the tunnel IIRC.