http://www.gtp.com.au/westbrew/inewsfiles/...l%20systems.pdf
Carbonation
The absorption of the CO2 into your beer depends on the temperature of
the beer, the pressure at which it is applied and the length of time
pressure is applied. The CO2 will be absorbed at a faster rate when the
beer is cold.
The standard method (3 days)
Connect the gas to your keg at 240kpa continually for 3 days under
normal refrigeration temperature (3oC). This should produce a correctly
carbonated beer. Gently reduce the pressure to the dispensing pressure
of 100kpa. Test for carbonation and leave for longer if required.
The long method (1 week)
If you are in no hurry to drink your beer you can connect your gas to the
keg at 100kpa (dispensing pressure) and leave it at this pressure for a
week in the fridge. By using this method you will not have to worry about
over carbonating your beer.
The super quick method (1 hour)
Once your keg is cold, turn the regulator to 300kpa and push the gas
connection slowly onto the beer outlet valve of the keg (pushing the
connection all the way on will cause it to get stuck) until you hear gas
going into the keg (it sounds like water boiling). With the gas line still
connected rock the upright keg back and forth for about 50 seconds. This
will help the beer absorb the CO2 much more readily as it bubbles up
through the beer. Next disconnect the gas and stand the keg in your
fridge for one hour to let the froth settle. After an hour pull the pressure
relief valve to release all pressure then connect at serving pressure
(100kpa). If your keg is not carbonated as much as you would like, repeat
the process but for 5-10 seconds at a time.
