Accidently mixed my beers when I connected the CO2 line.

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slayer021175666

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So, I have 2 corny kegs going. One had about 3 gallons of hefe in it fully carbonated and sitting at 10 lbs. The other was a stout that I force carbonated for 18 hrs at 35lb. Today, I woke up feeling tired and knew I had to stop force carbonating the stout. I came out to the fridge and hooked the co2 line back onto the hefe keg without turning down the pressure! I heard a hell of a noise and in an "oh SH#T!" moment I turned down the pressure to 10lbs. Now, my hefe has some stout in it! I thought the corny kegs had a check valve to stop beer from going up the co2 line. ??? Any insight or advice would be appreciated. Thanks.
 
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There are no check valves in kegs, they only exist in some regulator and manifold shut-off valves.

The only way beer could have been shipped from one keg to the other is if the donor was overfilled above the gas dip tube's reach. Might consider cutting the gas dip tube down to ~1/2" length to give you more headroom (close to an extra quart when cropped short). It only needs to be long enough to hold an O-ring, really. I did that to all of my kegs just on GPs.

As for the stouted hefe: come up with a clever style name and everyone will want it :)

Cheers!
 
Thanks. Good advice about the dip tube. Im always trying to cram more beer in the keg! As for the hefe-stout, you're right. It isn't terrible and we're gonna drink it. :)
 
Fyi. You can get gas disconnects with check valves in them. I use them for exactly this reason.
 
How did the stout actually get transferred from one keg to the other?
Unless you physically connected the two kegs to each other just disconnecting the gas line from one keg and attaching it to the other keg is not going to move any beer around. Maybe I misunderstood but if that's all you did then the noise you heard was just CO2 being forcefully pushed into the hefe keg beacause of the lower pressure in it.
 
Vale71,
My 2 kegs are on the same line. All I did was put a T-Fitting on the line to split it. I never turned down the pressure. I disconnected the hefe keg that only had 10lbs then, I connected the line to the stout keg and cranked it to 35lb. Once the stout keg was carbonated, I forgot to turn down the pressure before I re-connected the hefe keg. I believe what happened was, when I re-connected the hefe keg at the full 35lbs, stout at 35lb shot through the T-Fitting into the hefe keg because of the lower pressure in the hefe keg. The sound I heard was the 2 kegs equalizing pressure and since the stout keg was full of beer, some stout went up the gas tube through the T-Fittng and into the hefe keg.
 
Hmm, well, you will have definitely sent something to the hefe keg. Certainly some CO2 from the stout keg and some CO2 from the tank both. Beyond that...

If the stout keg was super full, enough to reach the CO2 line, then yep you probably did send some of that over as well. A sudden release of pressure could have allowed some stout foam to get created (?), and get sent over as well.

Normally a keg isn't quite that full, and no beer was moved. But thinking on it more, you're right, it could have happened.
 
With a stock gas dip tube on a cornelius keg, every ounce filled above 5 gallons is at risk of being blown back through the gas plumbing if appropriate caution is not employed.

The dip tube length was spec'd for a reason...

Cheers!
 
You should enjoy the blend and not worry about it too much. You learned something, and will probably not repeat. If both beers were good or even decent, you'll still have good beer.
 
If the gas line is clear its pretty obvious if beer went through. Some of us fill kegs until the beer comes out of the gas post, so it's a lot easier to happen than some may think. I have done this too, with a tee in the gas line, which is why I now use check valve gas disconnects. I trust that the OP knows what happened.
 
Vale71,
My 2 kegs are on the same line. All I did was put a T-Fitting on the line to split it. I never turned down the pressure. I disconnected the hefe keg that only had 10lbs then, I connected the line to the stout keg and cranked it to 35lb. Once the stout keg was carbonated, I forgot to turn down the pressure before I re-connected the hefe keg. I believe what happened was, when I re-connected the hefe keg at the full 35lbs, stout at 35lb shot through the T-Fitting into the hefe keg because of the lower pressure in the hefe keg. The sound I heard was the 2 kegs equalizing pressure and since the stout keg was full of beer, some stout went up the gas tube through the T-Fittng and into the hefe keg.
If that is the case then there was a physical connection between the kegs and if one was overfilled a transfer of liquid may occur. However not turning down the pressure on the regulator actually improved the situation because as soon as you connected the second, lower pressure keg the regulator started pushing CO2 into the line to compensate and this might have reduced the amount of liquid that was transferred before pressures finally equalized. Turning down the pressure on the regulator will not reduce the pressure on the keg as regulators (at least all those that I have seen) have a check valve to prevent gas from flowing back when pressure is dialed down without first detaching the line.
 
I would think the regulator would regulate whatever is on the downstream line, as long as the line isn't checked on the keg; it would be worthless to drop pressure otherwise. Do "beer" gas regulators put a check valve downstream on the regulator or line? My other concern here is if there was some liquid in the gas line at 35 lbs and you turn the line down to 10 lbs, what is to prevent that liquid from coming up the gas line back to the regulator other than gravity? It already shot to the other keg, probably went up the main line as well, especially if they were both full. A wet gas regulator would bother me more than dunkel hefe.
 
Most regulators can be obtained with a check valve integrated within the shut off valve.
But there are plenty that don't come with that feature as standard.

In this scenario if the OPs reg had a check that would (hopefully) prevent backwashing the reg itself, but obviously it wouldn't prevent shipping beer between kegs. That's the job of a manifold - with check valves :)

Cheers!
 
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