Originally Posted by FlyGuy
No, you are forgetting that you have to add grain to increase the gravity. If your mash water is set to be proportional to the grain (e.g., 1.25 qts/lb) then you are going to have a greater volume of first runnings from the mash, and will require less sparge water to reach your target pre-boil volume.
I'm a beersmith convert, so thanks for bearing with me.
I think I figured it out today on a single batch. I think I have to basically increase my lauter tun deadspace from .5 gallon to 2.5 gallons for Beersmith to come out with the correct numbers. I like to get my sparge volume as half of my pre boil size. For a 5 gallon batch my preboil volume is 7 gallons.
I'm not losing 2.5 gallons to my 48 quart cooler but whatever it takes to get Beersmith to come out with the correct numbers...