Filling Corney Keg @ Microbrewery

This is a Newb question cause I am a Newbie at kegging.

I plan on getting my corney keg filled up at a local microbrewery and they told me to make sure it was clean (check), sanitized (check), and pressurized (Not Checked).  I understand what they mean by pressurized, but a little unsure of the procedure.  My common sense tells me to put the lid on the keg and pump up for CO2 to around 30 PSI until I no longer hear the gas flowing…check for any leaks and then thats it.  Does the sound right?

Thanks in advance!

yes

Why 30 psi?

Just curious.

I’d guess that’s probably what they’re gonna push at, something like how a pressurized bottle filler would work.

I would think it’s because you want the keg to stay sealed.  Sometimes if there isn’t enough pressure, the gaskets won’t seat, and you’ll have a leak.  Obviously 30 psi is more than enough to get your keg sealed, however, If there is a big change in temperature it can greatly change the pressure inside the keg.  The brewery has to allow pressure out of the keg while filling it or else it might blow!

I guess I was thinking the beer would be chilled to serving temp and set for the proper CO2 volume for cornies and most home brew systems . . i.e. 12-15 psi.

But I suppose it’s really what suits the micro, and then it’s left to the end user to balance for their needs. . . and yes, bleeding the keg as it is filled!  :)

Thanks for the responses.

I think that since the beer will already be carbonated at the micro is also a reason why they say to pressurize the keg.  I said 30 PSI’s just because I figured it would pressurize the empty keg quicker…10 PSI would accomplish the same thing I guess.  When I bring the filled keg home and chill it, I will adjust it to around 10 PSI.

Thanks again!

But they’re gonna have to release the pressure on the keg to fill it, right?  I can’t see why they’d want it pressurized other than to make sure it isn’t leaking.

I think Denny’s right, they probably want to make sure it isn’t leaking as well as displace any oxygen so the beer doesn’t oxidize when they fill it?

I know some of you purge with CO2 to prevent oxidation when filling - could that be it?

My bet is on it just being able to ‘hold pressure’ though.

or both…pressure check and CO2 purge.

I really see no need to put more than 15 lbs. o’ charge on it. The micro is gonna have to bleed it off to balance anyway. They want enough pressure to control the flow from their tank into the corny . . not too much where CO2 bubbles back into their tank and not so little that the initial rush of beer from their tank turns to foam in the corny.

I’m sure all will be revealed when you show up with corny in tow!  :smiley:

I’m guessing it’s to keep down on excessive foaming in your keg and out of the pressure relief valve on your lid when relieving pressure in your keg during the transfer.

Thanks dhacker, i’ll fill it using 15 PSIs.

No prob . . and be sure to use some keg lube on the lid O-ring!  :slight_smile:

My guess is that they’ll fill it from a tap (so it’s just like a big steel growler).  So all that pressurizing will do is ensure that it’s sealed and that there’s no O2 in there which will be bad for their beer. 
Now, if they go ahead and counter pressure fill, then having the keg pre-pressurized would be helpful - one less step for them, but 30psi seems pretty excessive.