Thanks WildebeestAttack.After this sort of conditioning only the residual CO2 remains. What it also means is that the cask will draw air in from the cellar and in around 5-7 days the beer will spoil. (Some non-CAMRA approved pubs use a blanket CO2 system which buys them several weeks of sale time but upsets greatly the bearded trainspotters).
If I get a system like this working I might try to go the traditional "CAMRA approved" type of option for parties where the whole batch would be finished quickly but for my own consumption I'll probably have to add a squirt of co2 every now and then.
I figure that by the time I can afford a beer engine, I will also have been able to afford a kegging system
Cheers!
Jono.