How to deal with boil off to get the target yield

[Hawkbox]

I'm not sure I understand the full extent.

 

[Nosybear]

Although I do think users should know how the software works, why it gives the results it does. Yes, the Brew Session has a water calculator that gives you pretty close (within a cup) how much water you need to get a given volume of wort but it still helps to know how it got to the result.

 

[Hawkbox]

I definitely do not have my boil off numbers sorted out. My preboil numbers are checking out but my post boil numbers are all over the damned place.

 

[J A]

but it still helps to know how it got to the result

https://www.brewersfriend.com/2010/06/12/water-volume-management-in-all-grain-brewing/
From the link on the equipment profile management page.
There's a whole section of FAQs with info and links to articles available onsite, too.

 

[Ward Chillington]

So I just bottled a batch of brown but didn't use the recipe here but I did up the amount of strike water to 1.5 qt per pound of grain and did a 1 hour boil. The results were much better with just about 5 1/2 gallons into the bottles from the 7 1/4 gallons that went into the kettle.

 

[Craigerrr]

Nice! Did you hit your OG?

 

[sn00ky]

OP, lots of great feedback above there, awesome indeed. Reading thought posts like these is what helped me figure it out too. If you are looking for a ball park, post your kettle size, type, and heat source, and I bet you will get a few responses that will be within a quart or 2.

If you any control over your heat source, it helps. I run 5500 Watt element, with a variable control so that I can control from 0 to 5500 watts of power to the element. During the boil, I keep an eye on volume and gravity (half the boil should be half the volume boil off your expecting for example). If I find I am ahead or behind boil off, I turn up or down my heat source, which will increase or decrease my boil off rate.
It's for this reason, I tuned my system to boil at 4000 watts, so that I got room both ways.

Cheers!

 

[Ward Chillington]

So I watched the video.....good lesson...I took some notes and treated it like a big word problem of water loss and additions and here's what it boils down to....( hee hee...see what I did there?)

Strike Water
- Grain Absorption of about 1 pint per pound of grain
= First Runnings
+ Sparge Water
= Pre-boil volume
- Evaporation
= Post-boil volume
- Kettle loss Whirlpool Pile)
= Fermenter Volume
- Trub Loss
= Batch to bottle ...or keg volume

Mash Hacks suggested 1.25 qt per pound, I did 1.5

 

[Craigerrr]

Glad that helped, it gave me an understanding of the nuts and bolts of water calcs. Highly recommended using the "quick water calcs" here on BF just though which, as I believe nosy said usually comes within a cup or so.
Cheers