BTP Boil Volume

I'm pretty sure this is a really stupid question, but I need to ask it anyway.

When I'm setting up a recipe in BTP, I see a bigger volume going into the kettle than the numbers account for. For example, a "Brewing Classic Styles" recipe has a 7 gallon boil and a 6 gallon final volume...yet when I set my numbers for a 6 gallon final, with 1 gallon evap. per hour and 1 hour boil...it tells me 7.25 should be going into the boil.

I can only think of 3 possible explanations:

1) There is some setting for trub loss or something that I cannot find and I need some guidance.
2) The software is calculating the .25 gal difference because the final volume is at 68*F and the kettle volume is at 212*F (That would really amaze me if there is a .25 gal difference between the temps).
3) I have absolutely lost my mind.

Anyone?

Maybe I can simplify since I wasn't very clear in the OP. I set a 6 gal final volume. I set 1 gal evaporation per hour. I set a 1 hour boil. To me, that should make a pre-boil volume of 7 gallons. Beer Tools Pro tells me my volume should be 7.25 gallons. Why?

I dont use BTP, but every software has a # for trub loss, it also has a # for loss of volume due to wort shrinkage (after cooling it is about 4% of the volume)

It is compensating for trub and or shrinkage is my only thought, you can adjust those #s somewhere.

It's the volume shrinkage. The kettle vol is at 212 and the final is at 68F.

Why 212 however? It seems like a volume based upon the temp you fill the kettle makes more sense - 170F or so.

Good question

In the schedule section, all volume measurements are temperature dependent so it might specify 7.1 gallons of runnings but it will then show something like 7.25 gallons at boil. I think they just had to pick a single temp for the field and went with 212.

Thanks all.

samc said:

Why 212 however? It seems like a volume based upon the temp you fill the kettle makes more sense - 170F or so.

Click to expand...

I had the exact same thought, which is what made me ask. I'm still amazed that liquid water expands so much when heated...

Think about it this way, if they chose 165F, which would be about right for an all grain brewer, it would exclude extract brewers. 212 is a common temp in the boil kettle for all brewers.