almost no carb in keg

[jkatz419]

My keezer was full when it was time to rack my last beer so I decided to carb it with sugar in the keg for a few weeks at room temp (70). Now everything I read online, in books, and in BeerSmith said to use 1/2 the amount of sugar you would use if you were to bottle. I used about 2 oz of corn sugar in a 5G batch hoping for about 2.3 volumes of CO2. After adding the sugar water solution and racking the beer into the keg I sealed it up with 10 psi and let it sit for a month at 70 degrees. I monitored the pressure with a gauge, it started out at 10 (from the sealing) and gradually rose to 20 over 3 weeks and held steady there for the last week. Excitedly I put it into the keezer and let it cool for 2 days. The first 2 pints were full of yeast runoff as expected and the third came out clear BUT there was almost no carbonation! What went wrong? Not enough sugar? The yeast obviously ate what I gave them as the gauge showed more pressure building in the keg.

 

[JuanMoore]

I've found that I need ~85-90% of what I'd use to bottle, not 50%.