Ok, i had a faulty aricon compressor (Siezed), so had to drain the system and change the compressor. I did it straight away to avoid damge to the dryer. I also put a blast of one of those top up cans in to ensure it had some lube in the pipes to prevent any damage. I took it to get it refiled, they drained and refilled to the prescribed amount, no leaks, rad fan working, clutch kicking in and out with the econ switch, but no aircon. There are no codes on the Hvac unit and it is coded correctly. One of the alloy pipes by the firewall is slightly warmer that the other but thats it. It all seems to say its working, but it obviously isnt. Anyone offer any help?