[J1284]

Hello, I am new to this. Not new to drinking beer or using a keg, but New to hooking up a co2 tank. I just completed a home bar, complete with draft tap, co2 tank, all lines, hoses, etc. I do NOT have a refrigeration unit yet, but I am having a party this weekend in which I will be using a keg. Here is my question. Right now the keg is sitting in my garage getting cold. It averages around 35 degrees or so. When I bring it inside, what pressure should I set the co2 tank to and is there anything I need to know before I do this. The keg will only last the evening, so long term use with it is not important. Thanks!!!