Originally Posted by david_42
The 1.2-1.5 vols is probably based on 55F, not 38F.
The pressure from the regulator does not depend on temperature.
Where I get conflicting information is where people say to only lightly carb a nitro-beer to 1.2-1.5vols of CO2 (at ANY temperature), and yet when I ultimately hook up the mixed blend of gas I am sustaining a CO2 pressure of 8lbs (2.2vols) of CO2 (32psi with a mixed blend will be 24lbs of Nitrogen and 8lbs of CO2). My question is should I go with my gut and charge with 8lbs of CO2@38°F (2.2vols) until it is balanced, or will I end up over-carbing the beer for some reason - and if so, what IS the reason?
As far as the temperature question - if I have set my regulator to 8lbs of pressure at the tank (70°F) going into the cooler (38°F), is there a difference in the outcome of CO2 volume I will acheive in my beer if the CO2 tank was instead inside the cooler and also at 38°F? There is a 32° difference in temperature from the regulator at 8PSI outside the tank to the actual beer at 38°F inside the tank.
I know that force carbing a beer to a certain volume when both units (the keg and the tank) are at 70° calls for one pressure setting, and force carbing a beer to the same aformentioned volume when both units are at 38° calls for a far less pressure... If the tank is at 70° and the beer it is charging is at 38° - which pressure on the chart do I carb with - the 38° or the 70°? Or is there an equation for something in the middle?