Pressure at temperature

[vamesq]

What pressure should I force carbonate my keg at room temperature so when i chill my kegs to 3C i get 12 psi.
Is there a formula i can use?

 

[McKnuckle]

Hopefully you’ll be chilling to 3°C otherwise you’ll turn your beer into a block of ice. You might want to correct the temperature in order to get a good answer. But in the meantime, here is a chart you can reference.

 

[day_trippr]

Also, do not worry about the "so when I chill my kegs..." part.
A beer carbonated to 2.5 volumes at "room temperature" will still be at 2.5 volumes at serving temperature - or any other temperature - as long as the keg remains tight. Of course the CO2 pressures will be different at the two temperatures, but as long as they correspond to valid temperature + pressure points on the same Volumes of CO2 line through the chart it's all good...

Cheers!