John’s got a ‘new’ used keg on his hands. Before he can brew with it though we need to get it ready for service as a beer vessel. This week we go through the process of changing the o-rings on a corny keg.

When you are looking at used corny kegs (or new ones for that matter), a good retailer will have purged the keg with CO2 and left the keg under some pressure. When you pull up on the pressure relief valve (PRV) it should hiss a little as that pressure escapes. That lets you know the keg can and does indeed hold pressure with leaking somewhere. Thankfully, John’s keg did indeed do just that. So we know it will hold pressure.

When you stink your nose in a used keg you’ll probably get a goos CO2 sting up your nostrils. After you peel yourself off the floor and carefully smell it again, you’ll usually get the faint whiff of soda. Bonus points to you if you can identify the soda smell itself. In this day and age, its hard to believe your keg held soda recently, unless it came from some small boutique soda place. Many places do a quick cleansing rinse of the kegs prior to them getting shipped out.

So why do you still get a strong soda smell… its because the O-rings likely are holding quite a bit of soda aroma. The only solution is changing the o-rings. This includes the primary lid o-ring, the post o-rings and the dip tube o-rings. Many good homebrew shops sell refurbish o-ring kits.

For John’s keg changing all 5 o-rings took less than ten minutes. Time well spent to avoid having a grape Fanta infused porter. However, grape Fanta infused Saison doesn’t sound half bad.

Let us know how your keg maintenance process goes. How often do you change o-rings?

BREW ON!