Author Topic: Balancing a Nitro Draft System  (Read 263 times)

Offline Phil_M

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Balancing a Nitro Draft System
« on: March 10, 2019, 05:19:03 PM »
Anyone have info on this? Some basic searches are just coming up with the regular draft balancing formula. More specifically, I'm looking for the proper line length. My regular CO2 draft lines are shorter than the formula specifies for most beers, as I server at a far lower carbonation level than most. Need to know how that will impact a nitrogen based draft system, so I can order more beer line if needed.
Corn is a fine adjunct in beer.

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Online Robert

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Re: Balancing a Nitro Draft System
« Reply #1 on: March 10, 2019, 06:30:55 PM »
The BA's Draught Beer Quality Manual (download from the BA site,) particularly Appendix C, has plenty of geeky information that may help you calculate what you need.
Rob Stein
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Offline Phil_M

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Re: Balancing a Nitro Draft System
« Reply #2 on: March 10, 2019, 08:59:16 PM »
That deals with the whole getting the CO2 balance right when dealing with a mixed gas. That part I figured out already.

What I specifically need is to know the length of beer line needed to balance the system. I know the Guinness type taps have a restrictor that will help offset the increased serving pressure needed to properly carbonate the beer, but what part does line length serve?
Corn is a fine adjunct in beer.

And don't buy stale beer.

Online Robert

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Re: Balancing a Nitro Draft System
« Reply #3 on: March 10, 2019, 09:18:59 PM »
Does ch. 4, pp. 36 ff., of the manual cover what you need?  That's on balancing a mixed  gas system.  My intuition would be that total resistance  and total pressure would have to be in balance, just like a straight CO2 system, regardless of the proportional contributions to pressure of each gas.*  But I don't have expertise.  (Unfortunately my only practical experience with nitro was changing kegs and pouring Guinness long ago, never had to design a system.)

* If it's a simple as that, balancing a direct draw system is earlier in the manual.
« Last Edit: March 10, 2019, 09:31:16 PM by Robert »
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline Frankenbrew

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Re: Balancing a Nitro Draft System
« Reply #4 on: March 10, 2019, 10:10:43 PM »
I can only tell you what works for me. I have 5' lines and prepare the beer with 30psi for 24 hours which will give you a start (low carbonation and a 1" nitro head. Then, I turn the pressure down to 20psi which seems to maintain the carbonation and the head. I close the gas valve when I am not serving to prevent over carbonation. IMHO it works very well.
Frank C.

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heart, you brew good ale.'

Offline ynotbrusum

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Re: Balancing a Nitro Draft System
« Reply #5 on: March 11, 2019, 01:40:49 AM »
Check the NHC presentations from circa 2014 - I went to a seminar by Dr. Tom Schmidlin about line balancing.  My simple minded takeaway was that beer line is cheap so start on the long side and pare it back until it works, because beer line is relatively cheap.  Also switch out the stuff periodically for the same reason!  But he gives good technical info, too.
Hodge Garage Brewing: "Brew with a glad heart!"

Offline Phil_M

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Re: Balancing a Nitro Draft System
« Reply #6 on: March 11, 2019, 11:38:13 PM »
My takeaway from all this has been to have a longer length of beer line on hand, but that my 5' lines should be fine. If it isn't, start with 10' and technician it down from there, vs. trying to engineer the system.

Thanks for the help folks...parts start arriving tomorrow...we'll see how this goes.
Corn is a fine adjunct in beer.

And don't buy stale beer.