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Old 08-15-2012, 07:47 PM   #1
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OK - moving from 5 gal to 10 gal batches.

How big does the Brew Kettle really need to be?
15 gal or 20 gal

I think I have all the other major items covered - but the 10 gal kettle is not going to work.

I would like to hear everyone's thoughts.

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Old 08-15-2012, 07:59 PM   #2
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I have a 15 gallon kettle. I get about 2.25 gallons of boil off over a 90 minute boil, plus I leave about .5 gallon of sludge in the bottom, so I'm at a preboil volume of around 12.75 or so.

I have an 11 gallon kettle too that I used for a couple of 10 gallon batches and it required constant babysitting to avoid boil overs. I started with about 9.5 in the kettle and added the additional wort as it boiled off. Not fun and not best practice for sure.

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Old 08-17-2012, 03:36 PM   #3
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I have a converted keg (15.5 gal) that I routinely do 12 gallon batches in. For this kettle, I get about 1.5 gallons per hour of boil off. Starting with a 13.5 gallon pre boil volume I do have to watch through the hot break, but after that, there isn't a problem at all. If you ran across a converted keg, grab it. If you have a 15 gal and a 20 gal to choose from, get the 20 so that you can brew with a little more margin for error. Plus, if you do a really hoppy IPA, those extra hops will really suck up some volume and you might want to bump up your batch size to compensate.

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Old 08-17-2012, 05:15 PM   #4
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I brew 10gallons using a 50L (13ish gallon) brew kettle from a converted keg.

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Old 08-17-2012, 08:39 PM   #5
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Most our customers get the 15gal kettle for doing their 10gal batches.

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Old 08-17-2012, 08:52 PM   #6
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i had been using 13.2 gal for a year, its fine but you have to watch for boilovers, now i have full size keggle (15.5gal) and its much nicer, i dont see a point getting bigger BK for 10gal batches

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Old 08-17-2012, 09:00 PM   #7
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15.5 seems just about right for the 10 gal batches I've been doing.
The yeast knows what it's doing.

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Old 08-17-2012, 10:30 PM   #8
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I use a Stout 19.8 gallon kettle with recirculation fittings for my 10 gallon batches. I start with a little less than 13 gallons and end up filling 6 gallon carboys with 5.5g each. If you're going to use a converted keg a 15.5 gallons is just fine. Its just a matter of loss space in my kettle being higher due to the conical bottom.

That brings me to my real point. It depends on the design of your kettle and your ideal fermentation volume. I want to top off my kegs to just below the inlet stem so I'm generous about accounting for trub loss. I would suggest back calculating your boil volume from your fermenters to your kettle. Account for loss space in the kettle (reasonable loss is good here, room for break material to settle out) then add in a 2-3 gallons for boil over and stirring protection.

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Old 08-18-2012, 12:30 AM   #9
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If you have the option now, I'd go with the 20 gallon, just so you can do 15 gallon batches in the future.
I started doing 5 gallon batches, moved to 10, and now I'm wishing I could do 15 or 20 gallon batches.
If you make good beer, it WILL get consumed, regardless of the batch size it seems.

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