Looks like the low pressure valve on my air-con had a bit of a dummy spit and unseated itself enough to drop the gas in my system. There is still pressure so I'm fairly confident that I won't have moisture in the system. I've triggered the Schraeder valve and it seems to reseat and seal ok, so I need a die injection / regas to get my cold air back again.

Can anyone recommend anyone on the north side of Sydney - apart from a stealer - for a regas ?