Keg Gas Dynamics

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The Imperial Metric Brewery
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Ok well I thought I would finally put the T-piece on the gas line in the fridge today so I can pressure 2 kegs at once. Now I currently only have one tap.

Force carbonated 2 kegs, 1 x Oatmeal Stout, 1 x SFA. The oatmeal stout was about 5 deg cooler. (50 shakes each @ 350kPa). This was 2 hours ago.

Felt like tasting the stout so connected it to the tap. SFA & Stout connected to gas @ 100kpa, bottle on.

At this point I thought I would burp the stout keg a little incase the pressure was a bit high .... anyway SFA starts to flow in gas line into stout keg :eek:.

Hmm strange, level in keg shouldnt be high enuf for liquid to flow back! Oh well hit the tap and beer continues to flow! DIsconnected SFA and blew beer out of line ...

Anyone seen this before or is the SFA just keen to taste the stout also. :ph34r:
It should only do this for 2 reasons:

1. You're gassing in the beer line and when pressure in the other keg is dropped, the beer is forced out.
2. Your beer is above the gas dip tube.

How long is your gas dip tube? Or how full is the SFA? Is it possible that the SFA was still frothy from the shaking and hence was able to flow over to the other keg?

I have the same setup, just with T piece splitting the lines. And I have done the same transfer of beer between kegs. I added a nice ESB to a JB Premium clone that I had. Had them both connected and pulled a glass and thought gee that sounds weird.......oh sh#t. However the guilty keg had two dip tubes of equal length (liquid diptubes) instead of a short gas one (now rectified). I was aware of the possibility of it happening however this didn't prevent me actually doing it.

Anyway my advice now is make sure you sterilise your gas lines again incase you start growing mold in those lines which blows directly into both your kegs.

Well I think I will have to make the rash decision to drink 3 - 4 pints of SFA tonight to ensure the liquid is below the gas dip tube. :)
Doesn't matter if the gas tube is above or below the beer. When you have a high pressure and let it go all at once the beer froths up and the froth comes back to the reg.

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