How much carbonation is in my keg?

[LaundryBrew]

I have some carbonated Weizen in a keg which I racked this morning. Fermentation totalled 16 days. The first 7 days I used an airlock. For the remaining 9 days the FV was connected to 5 psi of CO2.
Is there a way to know how much carbonation already exists in the beer? I would like to complete the carbonation to a total of 3.9 volume of CO2.

 

[wsmith1625]

If you want to find the co2 volume, use the co2 volumes chart. You need to use the temperature the beer was fermenting at for the last 9 days and 5psi to calculate the co2 volume. This is good to know, but not necessary for getting to your final co2 volume. To get to your serving volume, use the chart again. This time, use your serving temperature and desired co2 volume to figure out what you need to set the regulator to. Then you have to wait for the co2 to absorb into the beer, which takes a week or 2 to finish. This is the set it and forget it method. You really can't mess this up. There are other methods to force carbonate your beer which are covered in detail in other HBT threads.

https://www.kegoutlet.com/keg-carbonation-chart.html

 

[DVCNick]

How much? Not much at all at ferm temp and 5psi. If it were me I would just treat it like any other beer that I transferred out of a non-pressurized fermenter.

 

[wsmith1625]

If you fermented at 65 degrees with 5lbs co2 you'll be at 1.11 which is undercarbed.

 

[Dustin_J]

EDIT: redundant

 

[MikeCo]

I would like to complete the carbonation to a total of 3.9 volume of CO2.

This is really high carbonation for a keg. You are likely to have a lot of foaming problems unless you have really long beer lines, like 25 feet.