Beer smith volumes

[sherma]

I think what you're saying is that if you start with 2 gal and boil off 0.9 gal, then you'd assume a 7-gal boil will also boil off 0.9 gal. I'm not sure that's true, due to the vagaries of heat transfer. But assuming it were, then you'd tell BS that the Evap Rate is 0.9/7 = 13%.

Simpler and more accurate is to just assume 15% then measure pre- and post-boil volumes during your next batch in order to refine the number. Done.

No, I don't think you want to do that. You want to go through this procedure for your boil kettle because each boil kettle will have a different boil off rate, mostly due to different surface areas between kettles.

It's true that if you boiled the same amount of water on 2 different days you would likely end up with slightly different boil off amounts, due to temperature and humidity, but that doesn't mean you should guess and just fudge your number in the software. It's a simple procedure to measure your boil off one time with water and use that in BeerSmith. No reason not to do it.

 

[SpeedYellow]

Seems you missed my point: boiling 2 gal will give you a different boil-off rate than boiling 7 gal. So I don't see this test as being any more accurate from simply assuming 15% then refining it a bit from the next batch. The error won't be any big deal. Plus you're not wasting time and energy required of this test. Just seems frivolous to me. Guess we'll have to agree to disagree.

 

[JeepDiver]

Thats true. However, as I have stated before, BS is calculating 6.53 Gal Pre-boil. 5.98 post-boil for a 5 fal batch. I get exactly 5 gal out of the kettle.

I guess my question is, am I supposed to get 5.98 gal into the fermenter at the calulated SG?

The batch size, is the amount in the fermenter, so if you are setting up for a 5 Gal batch, and you are getting 5 gallons, you are dead on.

If you look at The waterNeeded tool, it shows Boil and Fermentaion numbers. Boil Volume is your Pre Boil number (figured from the Mash section above).

You then have Boil Off, Loss to trub and Chiller, and Cooling Loss Rate (plus top off if your not doing full volume boil) that will give you Volume into Fermenter.

So somewhere you have .98 Gallons in the fields that count for your loss

The Losses in fermentation are for trub, etc that doesn't get bottled to give you the correct bottling amount

 

[ForestGroveBrewer]

You need to know your boil off rate and have it entered correctly. You also need to know the loss to trub and the amount of top up water into the fermentor. All of that is in the equipment profile and you need to set it specifically for your equipment.

I just looked at the equipment profile for "Pot and Cooler (5 gal/19 L) - All Grain" in BeerSmith. It's default settings are showing exactly the numbers you posted above for pre and post boil volumes. If that is the profile you are using, then you need to modify it to fit your situation. Modify everything on that tab to fit your equipment.

That could be my problem. When I upgraded to all-grain recently, I couldnt find a default equipment profile for 10 gal pot/ 10 gal (38L) cooler. So I copied 5gal/19L and renamed it. I thought I changed all the info to match my setup, but maybe missed something.

I will look and let you know.

Thanks!

 

[cluckk]

I checked my boil off rate by measuring eight gallons of water into the kettle at ambient temp and boiling for an hour. I then cooled back to ambient temp and measured the amount. I was barely off of BrewSmith's default numbers.