I would like to know the consesus of how much volume of beer is desirable when filing a keg, last time i filled almost 5 gallon and there was almost no head space, and i see this kind of risky like getting some beer to my gas line. any thoughts?
I figure any headspace you don’t absolutely need is just wasted. I fill until beer starts coming out the gas post, and just sanitize the gas disconnect I use for carbonating afterward.
I fill pretty full (basically, as full as I can get), but the risk of beer getting into the gasline is something to watch. The main thing I’ve found is that I’ve had to be careful with my pressure balance–i.e., make sure the pressure in the keg is always less than the pressure in my gas line-in, etc. I’ve had a few refluxes into the gas line over the years, and it’s annoying to have to change out the tubing.
To prevent fear of beer going up the gas line, I fill to just beneath the gas poppet diptube.
Same thing I do.
I have always thought back flow prevention was achieved by using check valves on gas lines (in my case, at the manifold). Ever since getting into kegging, this is the premise that I’ve operated under. If it’s true then it seems like cheap insurance to avoid back blow into the gas lines/disconnect/manifold/regulator (of course, this assumes that the check valve doesn’t fail :D).
Filled a keg up to the gas port one time. When the CO2 cylinder ran out, beer flowed up into the regulator. Ever since then I’ve installed check valves and kept the fluid level below the gas tube. Just takes one time to learn an expensive lesson.
I’m pretty certain my regulators came with check valves. It seems like less than best-practice not have them installed.
As far as filling, if I have less than 5 gallons I’ll try to use a 2.5 or 3 gallon keg. Anything excess can get bottled (which is a PITA, but doable). If I’ve got 4 gallons, they’ll go into a five gallon keg. I don’t need to bottle that much, but a sixer or so each batch is nice. I try not to have beer pouring out the gas tube, but it’s happened. Not the end of the world.
Really good advice, thanks!.
I do closed transfers, so what i will do is measure the amount of liquid in the keg when filling just beneath the gas poppet diptube. My fermentors are already marked with gallon levels so i have no problem guessing how much beer is filled in the keg, i can be more precise and use a weight scale.
BTW, you cursed me. I over filled a 2 gallon keg this weekend (beer coming out the gas side).
I had a couple kegs to carb and when I changed hoses from one keg to the next I got beer up into the gas line.
It didn’t hit the regulator, but I had to disassemble and clean my gas lines. Lovely.
Never happened to me before in about 10 years of kegging.
A 1" space below the cap is recommended.
If you have a used corny, make sure it is for 5 gallons volume. Many older “premix” tanks use by the soda industry were 4-1/2 gallons.
