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Trouble hitting the correct boil volume

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newbies13

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Hello, I seem to be having issues getting consistent final volumes of beer. I am guessing it's just disapearing during my boiling of the wort, but it seems to be so random.

For example I just did a peach heff with 7 gallons of water between mash and sparge. After a 60 minute boil I would say I have aprox 4 gallons of beer!

Thoughts?

My pot doesn't have any gallon markers so it's hard to tell exactly how much I wind up with, so I just eyeball what I wind up with in my carboy.
 

TheWitGuy

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How long is your boil? Did you account water absorption in the grains?
 

GashSlugg

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Make a simple measuring stick. If your boil is the same intensity can only be the grain or wrong measurements taken somewhere.
 

kiblerjd

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Typical grain absorption is around 0.5 qt/lb. So if you had about 12lb of grain you will lose 1.5 gallons of water. Then when you boil, depending on where you live, you will lose somewhere around 4qt/hr. So if you did and hour boil there is another gallon. You will also inevitably lose some amount of volume for miscellaneous loses such as dead space in the kettle and mash tun, tubing, etc. I always approximate 0.5gal for misc losses. So if you started with 7 gallons of water and ended with 4 gallons of beer I would say that is right on the money.

Are you new to all grain? There are 100 ways to skin a dead cat, but for me I build the recipes around how much I want in the kettle after the boil and that is how I figure out how much sparge water I need. So if I am making a 5 gallon batch I want 5.5 gallons left in the kettle after the boil and I work backwards from there with all of the losses factored in.

The easiest way to do this in reality is just make some extra sparge water and sparge until you have the desired volume in the kettle pre-boil. For a 5 gallon batch you are typically going to see about 4 gallons of mash water, and 4 gallons of sparge water (that is a very rough estimate). I hope this helps.

Take good notes while you brew and you will fine tune all of these losses and be able to plan for them pretty accurately.
 

GrogNerd

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measuring stick or aluminum yardstick

my BK is perfect: 30 qts and 15 inches tall -> 1" = 2 quarts, so measure and inchesx2 for quarts, inches÷2 for gallons
 

EarlyAmateurZymurgist

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Determining the exact amount of wort that is available in any cylindrical kettle at any given time in a boil is easy to do with the aid of a stainless steel ruler or measuring tape and a little math. All one needs to do is to know the inside diameter of one's kettle and the height of one's wort.

kettle_inside_radius = kettle_inside_diameter / 2

wort_volume_in_cubic_inches = wort_height x 3.14 x kettle_inside_radius x kettle_inside_radius

There are 231 cubic inches in a gallon; therefore, wort_volume_in_gallons = wort_volume_in_cubic_inches / 231.

Example:

kettle_inside_diameter = 14 inches

kettle_inside_radius = kettle_inside_radius / 2 = 7

wort_height = 8 inches

wort_volume_in_cubic_inches = 8 x 3.14 x 7 x 7 = 1231 cubic inches

wort_volume_in_gallons = 1231 / 231 ~= 5.33 gallons

Now, a quick and dirty way to know the approximate wort volume in gallons at any given point is to calculate the volume of one quarter inch of wort in gallons. Using the kettle diameter above, one_quarter_inch_of_wort_in_gallons = 0.25 x 3.14 x 7 x 7 / 231 = 0.1665 gallons per quarter inch of height, 1/3rd of a gallon per half inch of height, or one gallon for every 1.5 inches of height.

Tracking the height of one's wort every 15 minutes allows one make adjustments to the boil.

With that said, there are other factors that will limit the amount of wort that can be collected from one's kettle. Whole cone hops retain a significant amount of wort, as much as 12 fluid ounces of wort per ounce of hops. Additionally, break material that is left behind in the kettle will affect primary volume. The impact of break material and hops on primary volume should be tracked. Over time, one will be able to adjust for these losses on the fly without needing to perform any calculations. For example, I learned that I needed to boil down to one quart more than I expected to yield to my primary fermentor when brewing 5-gallon brews with up to two ounces of whole cone hops (i.e., boil down to 5.75 gallons to achieve a primary volume of 5.5 gallons).
 

EarlyAmateurZymurgist

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measuring stick or aluminum yardstick

my BK is perfect: 30 qts and 15 inches tall -> 1" = 2 quarts, so measure and inchesx2 for quarts, inches÷2 for gallons
One needs to be careful when blindly dividing the stated volume of one's kettle by the height of one's kettle. I use a Vollrath Optio 27 quart stock pot for 2.5 and 3-gallon batches. The stock pot is 12.5" tall by 12.5" wide. Using the equations shown above:

kettle_inside_diameter = 12.5 inches

kettle_inside_radius = kettle_inside_radius / 2 = 6.25

wort_height = 12.5 inches (the kettle filled to the brim)

wort_volume_in_cubic_inches = 12.5 x 3.14 x 6.25 x 6.25 = 1533 cubic inches

wort_volume_in_gallons = 1533 / 231 = 6.64 gallons

The Vollrath Optio 27-quart stock pot is classified as a 27-quart stock pot because Vollrath decided to be generous instead of being conservative when stating its volume. In reality, the Vollrath Optio 27-quart stock pot is a 26.5-quart stock pot. The only way to know for certain that one's kettle volume matches it's manufacturer stated volume is to measure and perform the calculations.
 

JDGator

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Hello, I seem to be having issues getting consistent final volumes of beer. I am guessing it's just disapearing during my boiling of the wort, but it seems to be so random.

For example I just did a peach heff with 7 gallons of water between mash and sparge. After a 60 minute boil I would say I have aprox 4 gallons of beer!

Thoughts?

My pot doesn't have any gallon markers so it's hard to tell exactly how much I wind up with, so I just eyeball what I wind up with in my carboy.
i use my mash paddle and added 1 gallon at a time and made a mark. i went all the way up to 15 marks in my 15.8 gallon pot. this way i can quickly add 10 gallons of water. if you want to be super accurate you could use 1/2 gallon marks.

You want to try to keep your boils consistent. not a raging boil one batch and then barely a boil the next. it will make a big difference in water evaporation.

Also write down all your volumes and temps. it may take you a few batches to figure out exactly what your boil off rate is. seems to be anywhere from 1.5-2.5gal/hr.
 

FuzzeWuzze

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i use my mash paddle and added 1 gallon at a time and made a mark. i went all the way up to 15 marks in my 15.8 gallon pot. this way i can quickly add 10 gallons of water. if you want to be super accurate you could use 1/2 gallon marks.

You want to try to keep your boils consistent. not a raging boil one batch and then barely a boil the next. it will make a big difference in water evaporation.

Also write down all your volumes and temps. it may take you a few batches to figure out exactly what your boil off rate is. seems to be anywhere from 1.5-2.5gal/hr.
This, if you dont have a reliable way to measure in 1 gallon at a time, or want to be extremely accurate use a home scale.

Each gallon of water should be like 8.3 pounds.
 
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N

newbies13

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The boils are pretty consistent I think, I just let it rapid boil, so I am guessing my pre boil volume is the culprit. I am going to have to measure out key gallon markers to ensure I am hitting my numbers instead of just relying on beer smiths calculations.

It seems like depending on the recipe I am hit and miss, and its so sad to see a full gallon of beer missing.
 

GrogNerd

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One needs to be careful when blindly dividing the stated volume of one's kettle by the height of one's kettle. I use a Vollrath Optio 27 quart stock pot for 2.5 and 3-gallon batches. The stock pot is 12.5" tall by 12.5" wide. Using the equations shown above:

kettle_inside_diameter = 12.5 inches

kettle_inside_radius = kettle_inside_radius / 2 = 6.25

wort_height = 12.5 inches (the kettle filled to the brim)

wort_volume_in_cubic_inches = 12.5 x 3.14 x 6.25 x 6.25 = 1533 cubic inches

wort_volume_in_gallons = 1533 / 231 = 6.64 gallons

The Vollrath Optio 27-quart stock pot is classified as a 27-quart stock pot because Vollrath decided to be generous instead of being conservative when stating its volume. In reality, the Vollrath Optio 27-quart stock pot is a 26.5-quart stock pot. The only way to know for certain that one's kettle volume matches it's manufacturer stated volume is to measure and perform the calculations.
the 30 qt, 15 inch thing didn't even occur to me until I was filling it up 2 quarts at a time and measuring. I was just going to write down the quantity vs measurement, print it up all pretty & laminate it or something.

it was 2 quarts & 1", 4 quarts & 2", 6 quarts & 3" and I might have been up to 2 gallons & 4" before I had my "duh" moment. but I kept up filling & measuring to the top and sure enough, 30 quarts = 15 inches. diameter = 12⅛"
 

EarlyAmateurZymurgist

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the 30 qt, 15 inch thing didn't even occur to me until I was filling it up 2 quarts at a time and measuring. I was just going to write down the quantity vs measurement, print it up all pretty & laminate it or something.

it was 2 quarts & 1", 4 quarts & 2", 6 quarts & 3" and I might have been up to 2 gallons & 4" before I had my "duh" moment. but I kept up filling & measuring to the top and sure enough, 30 quarts = 15 inches. diameter = 12⅛"
Many stock pots are right on the money. However, there are a few odd balls like the Optio 27 quart by Vollrath.

15 x 3.14 x 6.0625 x 6.0625 = 1731 cubic inches

1731 / 231 = 7.494 gallons, which is pretty much right on the money
 

MuddyCreek

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You could get ahold of Bobby and pick up a sight-glass for your kettle. Once you get that dialed in, you always know where your boil is at.

Then, do a few practice runs with simple water. Determine how much you have when you start boiling and how much you've got after 1 hour. That will make it easy to determine your boil-off rate and you can do some simple math from there to apply to your pre-boil volume.

Then you can even take your Pre-Boil Gravity and figure out what your OG should be after the boil.

Pretty easy once you do it a few times and get a decent idea what your actual boil-off rate is. (Course you need to set your boil rate at the same each time or the system breaks down...)
 

nebulous

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You could get ahold of Bobby and pick up a sight-glass for your kettle. Once you get that dialed in, you always know where your boil is at.

Then, do a few practice runs with simple water. Determine how much you have when you start boiling and how much you've got after 1 hour. That will make it easy to determine your boil-off rate and you can do some simple math from there to apply to your pre-boil volume.

Then you can even take your Pre-Boil Gravity and figure out what your OG should be after the boil.

Pretty easy once you do it a few times and get a decent idea what your actual boil-off rate is. (Course you need to set your boil rate at the same each time or the system breaks down...)
^what he said
through the first few batches i made my boil off seemed inconsistent but then i realized that the first time i did my measurements with plain water i didnt have my extractor fan on. once i realized that i found that i was boiling off over half a gallon more then with the fan off.
 
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