Water Boil Off Problem

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Attwell

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So I'm on to my second home brew very soon and have sorted most things out that I got wrong last time. Unfortunately last time I didn't record how much water I lose during the mash and boil etc... So my question is what do I do when it comes to water quantity with my brew if I don't know how much will boil off?

My Idea is this:

Mash In with 6 gallons like the recipe states, then when it comes to the sparge which says use an additional 6.5 gallons which will bring it to 12.5 gallons in total with an end result of 5 gallons... Instead of this I was thinking maybe sparge with 4 then just towards the end of the boil before I put the wort chiller in I'll take a gravity reading and see how much water I need to top the wort up with. The reason for this Is I don't want to have a brew that has to much water in, is this a good idea? Or do I top it up with water before transferring to fermenting bucket or do I just use what the recipe says?

Also should the water I use to top up be the same temp as the wort I'm putting it into?
 
I'm a little confused by your numbers there, I can't see how 12.5 gal. will end up with only 5 gal. after a boil of 60 to 90 min.
I mash with 20 lit. of water for a 5.5 kilo batch of grain. I drain this and get 15 to 16 lit in the boil kettle, I then dunk sparge / mash out with 12 to 13 lit at 80c' and drain this into the boil kettle - result is about 28 lit. and I have a loss of about 5 lit. during the boil.
So the liquid loss to grain absorption and boil off is about 10 lit max. for 23 to 24 lit batch of beer and that equates to 5 uk gal.
You can and should sparge with water at between 78 to 80c. for best results.
Cheers
 
That sounds like a huge amount of water. For a five gallon brew you should only be losing about half a gallon during the boil.
I'm doing BIAB in a 30L boiler. I usually do 4 gallon brews - 4 gallons approx. for the mash, another gallon for a dunk sparge. Boil for 90 minutes and a kettleful of boiling water to top up if necesary, either during the boil or in the FV.
 
That sounds like a huge amount of water. For a five gallon brew you should only be losing about half a gallon during the boil.
I'm doing BIAB in a 30L boiler. I usually do 4 gallon brews - 4 gallons approx. for the mash, another gallon for a dunk sparge. Boil for 90 minutes and a kettleful of boiling water to top up if necesary, either during the boil or in the FV.

What do you recommend with this brew then? Bare in mind I've got about 18oz of hops in this brew! Thanks for the advice!
 
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Can you post the recipe (grain bill) for this beer that would help any replies / advice, sounds like you have a large brew set up there!
Cheers

Sure no problem it's an 1868 East India Pale Ale:

- 17 pounds of Maris Otter Pale Ale Malt
- 18.9 oz of Fuggle Hops
- London Ale III Wy1318

Yield: 5 Gallons
OG: 1.067-1.069
FG: 1.012
IBU: 172 (Calculated)
 
That's a 7.7 kilo grain bill
Well running that through Brewers Friend gives -

5gal (23lit)
OG 1.078
FG 1.013
IBU 216.05
ABV 8.44%

Where did you get that from? I'm sure you will not need more than 32 lit. (7 gal.) of water in total for this
Tell you what though - once brewed and conditioned - no more than 2 pints a night :beer1::cheers3:

Cheers
 
That's a 7.7 kilo grain bill
Well running that through Brewers Friend gives -

5gal (23lit)
OG 1.078
FG 1.013
IBU 216.05
ABV 8.44%

Where did you get that from? I'm sure you will not need more than 32 lit. (7 gal.) of water in total for this
Tell you what though - once brewed and conditioned - no more than 2 pints a night :beer1::cheers3:

Cheers

From a Home Brew book mate by Mike Karnowski, how would you tackle this then? How many gallons should I use for Mash and Sparge? I hear ya mate gunna smash anther brew out after this one, need to get a grip of these calculators find them quite confusing aheadbutt
 
As a rough guide you want amount into fermenter + 1l per Kg grain + dead space in mash tun and boiler + boil off amount = total water needed. If you under estimate the boil off you can top up the water and its best done just before you turn the power off. If you can describe your equipment and sparge technique you could get a better answer.
 
As a rough guide you want amount into fermenter + 1l per Kg grain + dead space in mash tun and boiler + boil off amount = total water needed. If you under estimate the boil off you can top up the water and its best done just before you turn the power off. If you can describe your equipment and sparge technique you could get a better answer.

So I've got a 33 litre kettle and sparging technique I suspend the grain bag above the kettle and introduce more water depending on how much I need while also recirculating wort through the bag too.

So with a 5 gallon brew I would need 5 gallons plus a litre per kg of grain? What's dead space in mash tun and boiler?
 
For the mash, i put the correct amount of water in my boiler, taking in to account that the bottom of the bolier still has 1.75 litres in there.
I have this written on the lid, so I don't forget. (1.75l losses)
For the sparge, I fill my boiler in excess of what I need and stop sparging when my vessel shows that I reached my target.

Any wort left in the mash tun will be drained off to top up the boil.
 
For the mash, i put the correct amount of water in my boiler, taking in to account that the bottom of the bolier still has 1.75 litres in there.
I have this written on the lid, so I don't forget. (1.75l losses)
For the sparge, I fill my boiler in excess of what I need and stop sparging when my vessel shows that I reached my target.

Any wort left in the mash tun will be drained off to top up the boil.

So you put the amount of litres in the kettle for the batch your brewing then add 1.75 to account for boil off etc?
 
So you put the amount of litres in the kettle for the batch your brewing then add 1.75 to account for boil off etc?

I think the 1.75L is his dead space below the tap - ie wort that stays in boiler unless you just tip the whole lot in the FV. Typical boil off would maybe be 4-5L an hour depending on system.

So for 5kg of grain I would typically mash with 15L and sparge with 18L. I would lose 5L to grain absorption; 5L to boil off; 2L to dead space and maybe some to hop absorption and be left with about 21L in the FV.
 
I think the 1.75L is his dead space below the tap - ie wort that stays in boiler unless you just tip the whole lot in the FV. Typical boil off would maybe be 4-5L an hour depending on system.

So for 5kg of grain I would typically mash with 15L and sparge with 18L. I would lose 5L to grain absorption; 5L to boil off; 2L to dead space and maybe some to hop absorption and be left with about 21L in the FV.

So the amount of water you use in your brews are quite similar to the amount of water my recipe is telling me to use but everyone else that's commented on this has said that using that much water is crazy? Unless I've read it wrong and you mash with 15l and sparge with 3l not another 18?
 
Try using grainfather app. It works brilliantly and you can add 10 recipes for free.

You will need to set up your equipment profile but for anything you dont know a close guess will do. Next brew use the actual values obtained from this one.
The losses will come from:

Kettle dead space - whats left over in the kettle.
Boil off - usually 3-5L/hr
Grain absorbtion - safe to estimate 1L/kg grain.
 
So the amount of water you use in your brews are quite similar to the amount of water my recipe is telling me to use but everyone else that's commented on this has said that using that much water is crazy? Unless I've read it wrong and you mash with 15l and sparge with 3l not another 18?

Dont think so - werent you talking about 12.5 gallons total water which is 56 litres? The sparge is 18L in my example.
 
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When I do a full volume mash and looking for 23 litres into the fermenter with around the 5 kg grain bill a 90 minute mash and a 90 minute boil I mash into 34 litres of water, I lose, 0,800 litres to grain and 7.5 litres evaporation.
 
From a Home Brew book mate by Mike Karnowski, how would you tackle this then? How many gallons should I use for Mash and Sparge? I hear ya mate gunna smash anther brew out after this one, need to get a grip of these calculators find them quite confusing aheadbutt

I think you will find that Mikes book is a US publication and he will use US gals (I may be wrong) but you can check this out
As 1 gal US is about 3.79 lit. that's still 68 lit. - still about twice as much water than you will need
Cheers
 
OK, so by simple numbers - total amount of water for a 25L brew with 5kg of grain is 25 (the final volume), plus 2L for deadspace, plus 3L for boil-off, plus 5L for grain absorption equals 35 Litres altogether. Using an All-in-one system that might be 17L in the mash and 18L for the sparge. Unless you use the metric system, you will be hopelessly lost. Totally lose "imperial" or US measurements for anything even remotely scientific. Like cooking, brewing, or basically anything that involves computations. The great beauty of metric measures is that 1L of water weighs 1kg and water at 20C is 1.000 on the hydrometer.
 

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